Emerging technologies are technologies whose development, practical applications, or both are still largely unrealized. These technologies are generally new
but also include old technologies finding new applications. Emerging
technologies are often perceived as capable of changing the status quo.
Emerging technologies are characterized by radical novelty (in
application even if not in origins), relatively fast growth, coherence,
prominent impact, and uncertainty and ambiguity.
Emerging technologies include a variety of technologies such as information technology, nanotechnology, biotechnology, robotics, and artificial intelligence. New technological fields may result from the technological convergence
of different systems evolving towards similar goals. Convergence brings
previously separate technologies such as voice (and telephony
features), data (and productivity applications) and video together so
that they share resources and interact with each other, creating new
efficiencies.
Emerging technologies are those technical innovations which represent progressive developments within a field for competitive advantage; converging technologies represent previously distinct fields which are
in some way moving towards stronger inter-connection and similar goals.
However, the opinion on the degree of the impact, status and economic
viability of several emerging and converging technologies varies.
In the history of technology, emerging technologies are contemporary advances and innovation in various fields of technology.
Over centuries innovative
methods and new technologies have been developed and opened up. Some of
these technologies are due to theoretical research, and others from
commercial research and development.
Technological growth includes incremental developments and disruptive technologies. An example of the former was the gradual roll-out of DVD (digital video disc) as a development intended to follow on from the previous optical technology compact disc.
By contrast, disruptive technologies are those where a new method
replaces the previous technology and makes it redundant, for example,
the replacement of horse-drawn carriages by automobiles and other
vehicles.
Many writers, including computer scientistBill Joy, have identified clusters of technologies that they consider critical to
humanity's future. Joy warns that the technology could be used by
elites for good or evil.
They could use it as "good shepherds" for the rest of humanity or
decide everyone else is superfluous and push for the mass extinction of
those made unnecessary by technology.
Advocates of the benefits of technological change typically see emerging and converging technologies as offering hope for the betterment of the human condition. Cyberphilosophers Alexander Bard and Jan Söderqvist argue in The Futurica Trilogy that while Man himself is basically constant throughout human history (genes change very slowly), all relevant change is rather a direct or indirect result of technological innovation (memes change very fast) since new ideas always emanate from technology use and not the other way around. Man should consequently be regarded as history's main constant and
technology as its main variable. However, critics of the risks of
technological change, and even some advocates such as transhumanist philosopher Nick Bostrom, warn that some of these technologies could pose dangers, perhaps even contribute to the extinction of humanity itself; i.e., some of them could involve existential risks.
Some analysts such as Martin Ford argue that as information
technology advances, robots and other forms of automation will
ultimately result in significant unemployment as machines and software begin to match and exceed the capability of workers to perform most routine jobs.
As robotics and artificial intelligence develop further, even many
skilled jobs may be threatened. Technologies such as machine learning may ultimately allow computers to do many knowledge-based jobs that
require significant education. This may result in substantial
unemployment at all skill levels, stagnant or falling wages for most
workers, and increased concentration of income and wealth as the owners
of capital capture an ever-larger fraction of the economy. This in turn
could lead to depressed consumer spending
and economic growth as the bulk of the population lacks sufficient
discretionary income to purchase the products and services produced by
the economy.
Artificial intelligence (AI) is the sub intelligence exhibited by machines or software, and the branch of computer science
that develops machines and software with animal-like intelligence.
Major AI researchers and textbooks define the field as "the study and
design of intelligent agents," where an intelligent agent is a system that perceives its environment and takes actions that maximize its chances of success. John McCarthy, who coined the term in 1956, defines it as "the study of making intelligent machines".
The central functions (or goals) of AI research include reasoning, knowledge, planning, learning, natural language processing (communication), perception and the ability to move and manipulate objects. General intelligence (or "strong AI")
is still among the field's long-term goals. Currently, popular
approaches include deep learning, statistical methods, computational
intelligence and traditional symbolic AI. There is an enormous number of
tools used in AI, including versions of search and mathematical
optimization, logic, methods based on probability and economics, and
many others.
Combined with Internet technology, 3D printing allows for digital
blueprints of various material products to be sent instantly to another
person to be produced on the spot.
Although this technology is still too crude to produce most
products, it is rapidly developing and created a controversy in 2013
around the issue of 3D printed firearms.
Gene therapy was first successfully demonstrated in late 1990/early 1991 for adenosine deaminase deficiency,
though the treatment was somatic – that is, did not affect the
patient's germ line and thus was not heritable. This led the way to
treatments for other genetic diseases and increased interest in germ line gene therapy – therapy affecting the gametes and descendants of patients.
Between September 1990 and January 2014, there were around 2,000 gene therapy trials conducted or approved.
A cancer vaccine is a vaccine that treats existing cancer
or prevents the development of cancer in certain high-risk individuals.
Vaccines that treat existing cancer are known as therapeutic cancer
vaccines. There are currently no vaccines able to prevent cancer in
general.
On April 14, 2009, The Dendreon Corporation announced that their Phase III clinical trial of Provenge, a cancer vaccine designed to treat prostate cancer, had demonstrated an increase in survival. It received U.S. Food and Drug Administration (FDA) approval for use in the treatment of advanced prostate cancer patients on April 29, 2010. The approval of Provenge has stimulated interest in this type of therapy.
Cultured meat, also called in vitro meat, clean meat,
cruelty-free meat, shmeat, and test-tube meat, is an animal-flesh
product that has never been part of a living animal with exception of
the fetal calf serum taken from a slaughtered cow. In the 21st century, several research projects have worked on in vitro meat in the laboratory. The first in vitro beefburger, created by a Dutch team, was eaten at a demonstration for the press in London in August 2013. There remain difficulties to be overcome before in vitro meat becomes commercially available. Cultured meat is prohibitively expensive, but it is expected that the
cost could be reduced to compete with that of conventionally obtained
meat as technology improves. In vitro
meat is also an ethical issue. Some argue that it is less objectionable
than traditionally obtained meat because it does not involve killing
and reduces the risk of animal cruelty, while others disagree with
eating meat that has not developed naturally.
Nanotechnology is the manipulation of matter on an atomic, molecular, and supramolecular scale. The earliest widespread description of nanotechnology referred to the particular technological goal of precisely
manipulating atoms and molecules for fabrication of macroscale products,
also now referred to as molecular nanotechnology. A more generalized description of nanotechnology was subsequently established by the National Nanotechnology Initiative, which defines nanotechnology as the manipulation of matter with at least one dimension sized from 1 to 100 nanometers. This definition reflects the fact that quantum mechanical
effects are important at this scale, and so the definition shifted from
a particular technological goal to a research category inclusive of all
types of research and technologies that deal with the special
properties of matter that occur below the given size threshold.
Robotics is the branch of technology that deals with the design, construction, operation, and application of robots, as well as computer systems for their control, sensory feedback, and
information processing. These technologies deal with automated machines
that can take the place of humans in dangerous environments, factories,
warehouses, or kitchens; or resemble humans in appearance, behavior,
and/or cognition. A good example of a robot that resembles humans is Sophia, a social humanoid robot developed by Hong Kong-based company Hanson Robotics which was activated on April 19, 2015. Many of today's robots are inspired by nature contributing to the field of bio-inspired robotics.
Stem cell therapy is an intervention strategy that introduces new
adult stem cells into damaged tissue in order to treat disease or
injury. Many medical researchers believe that stem cell treatments have the potential to change the face of human disease and alleviate suffering. The ability of stem cells to self-renew and give rise to subsequent generations with variable degrees of differentiation capacities offers significant potential for generation of tissues that can
potentially replace diseased and damaged areas in the body, with minimal
risk of rejection and side effects.
Chimeric antigen receptor (CAR)-modified T cells have raised
among other immunotherapies for cancer treatment, being implemented
against B-cell malignancies. Despite the promising outcomes of this
innovative technology, CAR-T cells are not exempt from limitations that
must yet to be overcome in order to provide reliable and more efficient
treatments against other types of cancer.
Distributed ledger or blockchain technology provides a transparent
and immutable list of transactions. A wide range of uses has been
proposed for where an open, decentralised database is required, ranging
from supply chains to cryptocurrencies.
Smart contracts
are self-executing transactions which occur when pre-defined conditions
are met. The aim is to provide security that is superior to traditional
contract law, and to reduce transaction costs and delays. The original
idea was conceived by Nick Szabo in 1994, but remained unrealised until the development of blockchains.
This technology, which overlays digital graphics onto live footage,
has existed since the late 20th century. However, with the development
of more powerful computing hardware and the growth of open-source
software, its capabilities have expanded far beyond what was once
thought possible. Today, it is widely used in applications such as
Pokémon Go, Snapchat and Instagram filters, and other platforms that
integrate fictional or digital elements into real-world environments.
Reusable rockets, in contrast to single use rockets that are disposed
after launch, are able to propulsively land safely in a pre-specified
place where they are recovered to be used again in later launches. Early
prototypes include the McDonnell Douglas DC-X tested in the 1990s, but the company SpaceX was the first to use propulsive reusability on the first stage of an operational orbital launch vehicle, the Falcon 9, in the 2010s. SpaceX is also developing a fully reusable rocket known as Starship. Other companies developing reusable rockets include Blue Origin and Rocket Lab.
Development of emerging technologies
As innovation drives economic growth, and large economic rewards come
from new inventions, a great deal of resources (funding and effort) go
into the development of emerging technologies. Some of the sources of
these resources are described below.
Applied research
is a form of systematic inquiry involving the practical application of
science. It accesses and uses some part of the research communities'
(the academia's) accumulated theories, knowledge, methods, and
techniques, for a specific, often state-, business-, or client-driven
purpose.
Science policy
is the area of public policy which is concerned with the policies that
affect the conduct of the science and research enterprise, including the
funding of science, often in pursuance of other national policy goals
such as technological innovation to promote commercial product
development, weapons development, health care and environmental
monitoring.
Patents
Top 30 AI patent applicants in 2016
Patents
provide inventors with a limited period of time (minimum of 20 years,
but duration based on jurisdiction) of exclusive right in the making,
selling, use, leasing or otherwise of their novel technological
inventions. Artificial intelligence,
robotic inventions, new material, or blockchain platforms may be
patentable, the patent protecting the technological know-how used to
create these inventions.
In 2019, the World Intellectual Property Organization (WIPO) reported that AI was the most prolific emerging technology in terms of number of patent applications and granted patents, the Internet of things
was estimated to be the largest in terms of market size. It was
followed, again in market size, by big data technologies, robotics, AI,
3D printing and the fifth generation of mobile services (5G). Since AI emerged in the 1950s, 340,000 AI-related patent applications
were filed by innovators and 1.6 million scientific papers have been
published by researchers, with the majority of all AI-related patent
filings published since 2013. Companies represent 26 out of the top 30
AI patent applicants, with universities or public research organizations
accounting for the remaining four.
DARPA
DARPA
(Defense Advanced Research Projects Agency) is an agency of the U.S.
Department of Defense responsible for the development of emerging
technologies for use by the military.
DARPA was created in 1958 as the Advanced Research Projects
Agency (ARPA) by President Dwight D. Eisenhower. Its purpose was to
formulate and execute research and development projects to expand the
frontiers of technology and science, with the aim to reach beyond
immediate military requirements.
Projects funded by DARPA have provided significant technologies that have influenced many non-military fields, such as the Internet and Global Positioning System technology.
Technology competitions and awards
There are awards that provide incentive to push the limits of
technology (generally synonymous with emerging technologies). Note that
while some of these awards reward achievement after-the-fact via
analysis of the merits of technological breakthroughs, others provide
incentive via competitions for awards offered for goals yet to be
achieved.
The Orteig Prize was a $25,000 award offered in 1919 by French hotelier Raymond Orteig for the first nonstop flight between New York City and Paris. In 1927, underdog Charles Lindbergh won the prize in a modified single-engine Ryan aircraft called the Spirit of St. Louis. In total, nine teams spent $400,000 in pursuit of the Orteig Prize.
The XPRIZE series of awards, public competitions designed and managed by the non-profit organization called the X Prize Foundation,
are intended to encourage technological development that could benefit
mankind. The most high-profile XPRIZE to date was the $10,000,000 Ansari
XPRIZE relating to spacecraft development, which was awarded in 2004
for the development of SpaceShipOne.
The Turing Award is an annual prize given by the Association for Computing Machinery
(ACM) to "an individual selected for contributions of a technical
nature made to the computing community." It is stipulated that the
contributions should be of lasting and major technical importance to the
computer field. The Turing Award is generally recognized as the highest
distinction in computer science, and in 2014 grew to $1,000,000.
In 2003, David Gobel seed-funded the Methuselah Mouse Prize
(Mprize) to encourage the development of new life extension therapies
in mice, which are genetically similar to humans. So far, three Mouse
Prizes have been awarded: one for breaking longevity records to Dr.
Andrzej Bartke of Southern Illinois University; one for late-onset rejuvenation strategies to Dr. Stephen Spindler of the University of California; and one to Dr. Z. Dave Sharp for his work with the pharmaceutical rapamycin.
Science fiction has often affected innovation
and new technology by presenting creative, intriguing possibilities for
technological advancement. For example, many rocketry pioneers were
inspired by science fiction. The documentary How William Shatner Changed the World describes a number of examples of imagined technologies that became real.
The term bleeding edge has been used to refer to some new technologies, formed as an allusion to the similar terms "leading edge" and "cutting edge". It tends to imply even greater advancement, albeit at an increased risk because of the unreliability of the software or hardware. The first documented example of this term being used dates to early
1983, when an unnamed banking executive was quoted to have used it in
reference to Storage Technology Corporation.
The percentage of marine animal extinction at the genus level through the six mass extinctions
Two men next to a pile of American bison skulls awaiting industrial processing and conversion into fertilizer in the United States, in 1892.The dodo
became extinct during the mid-to-late 17th century because of habitat
destruction, overhunting, and predation by introduced mammals. It is an often-cited example of a human-driven extinction.
The Holocene or Anthropocene extinction is an ongoing extinction event caused by human activity during the current geological epoch, impacting diverse families of plantsand animals, including mammals, birds, reptiles, amphibians, fish, and invertebrates, as well as both terrestrial and marine species. It is sometimes also called the sixth extinction (though this can also describe the Capitanian).
Major extinction events during this period have been recorded across all continents, including Africa, Asia, Europe, Australia, North and South America, and various islands.
Overview
The moa in New Zealand went extinct in the mid 15th century because of overhunting and habitat destruction by the Māori people. Prior to the arrival of the Māori a century earlier, New Zealand was uninhabited by humans.
Mass extinctions are characterized by the loss of at least 75% of species within a geologically short period of time (i.e., less than 2 million years). The Holocene is the current geological epoch.
The precise timing of the Holocene extinction event remains
debated, with no clear consensus on when it began or whether it should
be considered distinct from the Quaternary extinction event.However, most scientists agree that human activities are the primary driver of the Holocene extinction.A 1998 survey conducted by the American Museum of Natural History found that 70% of biologists acknowledged an ongoing anthropogenic extinction event. Some researchers suggested that the activities of earlier archaic humans may have contributed to earlier extinctions, especially in Australia, New Zealand, and Madagascar. Even modest hunting pressure, combined with the vulnerability of large animals on isolated islands, is thought to have been enough to wipe out entire species. Only in the more recent stages of the Holocene have plants suffered extensive losses, which are also linked to human activities such as deforestation and land conversion.
Extinction rate
The contemporary rate of extinction is estimated at 100 to 1,000 times higher than the natural background extinction rate—the typical rate of species loss through natural evolutionary processes. One estimation suggested the rate could be as high as 10,000 times the background extinction rate, though this figure remains controversial. Theoretical ecologistStuart Pimm has noted that the extinction rate for plants alone is 100 times higher than normal.
While some argue that the current extinction rates have not yet reached the catastrophic levels of past mass extinctions, Barnosky
et al. (2011) and Hull et al. (2015) points out that extinction rates
during past mass extinctions cannot be fully determined because of gaps
in the fossil record. However, they agree that the ongoing biodiversity loss is nonetheless unprecedented. Estimates of species lost per year vary widely—from 1.5 to 40,000
species—but all indicate that human activity is driving this crisis.
In The Future of Life (2002), biologist Edward Osborne Wilson
predicted that, if current trend continues, half of Earth's higher
lifeforms could be extinct by 2100. More recent studies further support
this view. A 2015 study on Hawaiian snails suggested that up to 7% of
Earth's species may already be extinct. A 2021 study also found that only around 3% of the planet's terrestrial surface remains ecologically and faunally intact—areas that still have healthy populations of native species and minimal human footprint.A 2022 study suggests that if global warming continues, between 13% and
27% of terrestrial vertebrate species could be driven to extinction by
2100, with habitat destructions and co-extinctions accounting for the rest.
The 2019 Global Assessment Report on Biodiversity and Ecosystem Services, published by the United Nations IPBES, estimated that about one million species are currently at risk of extinction within decades because of human activities.Organized human existence is jeopardised by increasingly rapid
destruction of the systems that support life on Earth, according to the
report, the result of one of the most comprehensive studies of the
health of the planet ever conducted. Moreover, the 2021 Economics of Biodiversity review, published by the UK government, asserts that "biodiversity is declining faster than at any time in human history. According to a 2022 study published in Frontiers in Ecology and the Environment,
a survey of more than 3,000 experts says that the extent of the mass
extinction might be greater than previously thought, and estimates that
roughly 30% of species "have been globally threatened or driven extinct
since the year 1500." In a 2022 report, IPBES listed unsustainable fishing, hunting, and logging as some of the primary drivers of the global extinction crisis.
A 2023 study published in PLOS One shows that around two million species are threatened with extinction, double the estimate put forward in the 2019 IPBES report. According to a 2023 study published in PNAS, at least 73 genera
of animals have gone extinct since 1500. If humans had never existed,
the study estimates it would have taken 18,000 years for the same genera
to have disappeared naturally, leading the authors to conclude that
"the current generic extinction rates are 35 times higher than expected
background rates prevailing in the last million years under the absence
of human impacts" and that human civilization is causing the "rapid
mutilation of the tree of life."
Attribution
We are currently, in a systematic manner, exterminating all non-human living beings.
There is widespread consensus among scientists that human
activities—especially habitat destruction, resource consumption, and the
elimination of species—are the main drivers of the current extinction
crisis. Rising extinction rates among mammals, birds, reptiles, amphibians, and
other groups have led many scientists to declare a global biodiversity
crisis.
The description of recent extinction as a mass extinction has been debated among scientists. Stuart Pimm, for example, asserts that the sixth mass extinction "is something that hasn't happened yet—we are on the edge of it." Several studies posit that the Earth has entered a sixth mass extinction event, including a 2015 paper by Barnosky et al. and a November 2017 statement titled "World Scientists' Warning to Humanity: A Second Notice",
led by eight authors and signed by 15,364 scientists from 184 countries
which asserted, among other things, that "we have unleashed a mass
extinction event, the sixth in roughly 540 million years, wherein many
current life forms could be extirpated or at least committed to
extinction by the end of this century." The World Wide Fund for Nature's 2020 Living Planet Report says that wildlife populations have declined by 68% since 1970 as a result of overconsumption, population growth, and intensive farming,
which is further evidence that humans have unleashed a sixth mass
extinction event; however, this finding has been disputed by one 2020
study, which posits that this major decline was primarily driven by a
few extreme outlier populations, and that when these outliers are
removed, the trend shifts to that of a decline between the 1980s and
2000s, but a roughly positive trend after 2000. A 2021 report in Frontiers in Conservation Science
which cites both of the aforementioned studies, says "population sizes
of vertebrate species that have been monitored across years have
declined by an average of 68% over the last five decades, with certain
population clusters in extreme decline, thus presaging the imminent
extinction of their species," and asserts "that we are already on the
path of a sixth major extinction is now scientifically undeniable." A January 2022 review article published in Biological Reviews
builds upon previous studies documenting biodiversity decline to assert
that a sixth mass extinction event caused by anthropogenic activity is
currently under way. A December 2022 study published in Science Advances
states that "the planet has entered the sixth mass extinction" and
warns that current anthropogenic trends, particularly regarding climate
and land-use changes, could result in the loss of more than a tenth of plant and animal species by the end of the century.12% of all bird species are threatened with extinction. A 2023 study published in Biological Reviews
found that, of 70,000 monitored species, some 48% are experiencing
population declines from anthropogenic pressures, whereas only 3% have
increasing populations.
According to the UNDP's 2020 Human Development Report, The Next Frontier: Human Development and the Anthropocene:
The planet's biodiversity is
plunging, with a quarter of species facing extinction, many within
decades. Numerous experts believe we are living through, or on the cusp
of, a mass species extinction event, the sixth in the history of the
planet and the first to be caused by a single organism—us.
The 2022 Living Planet Report found that vertebrate wildlife
populations have plummeted by an average of almost 70% since 1970, with
agriculture and fishing being the primary drivers of this decline.
Some scientists, including Rodolfo Dirzo and Paul R. Ehrlich,
contend that the sixth mass extinction is largely unknown to most
people globally and is also misunderstood by many in the scientific
community. They say it is not the disappearance of species, which gets
the most attention, that is at the heart of the crisis, but "the
existential threat of myriad population extinctions."
A diagram showing the ecological processes of coral reefs before and during the Anthropocene
The abundance of species extinctions considered anthropogenic,
or due to human activity, has sometimes (especially when referring to
hypothesized future events) been collectively called the "Anthropocene
extinction". Anthropocene is a term introduced in 2000. Some now postulate that a new geological epoch has begun, with the most abrupt and widespread extinction of species since the Cretaceous–Paleogene extinction event 66 million years ago.
The term "anthropocene" is being used more frequently by
scientists, and some commentators may refer to the current and projected
future extinctions as part of a longer Holocene extinction. The Holocene–Anthropocene boundary is contested, with some commentators
asserting significant human influence on climate for much of what is
normally regarded as the HoloceneEpoch. Some experts mark the transition from the Holocene to the Anthropocene at the onset of the industrial revolution.
They also note that the official use of this term in the near future
will heavily rely on its usefulness, especially for Earth scientists
studying late Holocene periods.
It has been suggested that human activity has made the period
starting from the mid-20th century different enough from the rest of the
Holocene to consider it a new geological epoch, known as the Anthropocene, a term which was considered for inclusion in the timeline of Earth's history by the International Commission on Stratigraphy in 2016, but the proposal was rejected in 2024. To constitute the Holocene as an extinction event, scientists must determine exactly when anthropogenic greenhouse gas emissions
began to measurably alter natural atmospheric levels on a global scale,
and when these alterations caused changes to global climate. Using
chemical proxies from Antarctic ice cores, researchers have estimated
the fluctuations of carbon dioxide (CO2) and methane (CH4) gases in the Earth's atmosphere during the Late Pleistocene and Holocene epochs. Estimates of the fluctuations of these two gases in the atmosphere,
using chemical proxies from Antarctic ice cores, generally indicate that
the peak of the Anthropocene occurred within the previous two
centuries: typically beginning with the Industrial Revolution, when the highest greenhouse gas levels were recorded.
A 2015 article in Science
suggested that humans are unique in ecology as an unprecedented "global
superpredator", regularly preying on large numbers of fully grown
terrestrial and marine apex predators, and with a great deal of influence over food webs and climatic systems worldwide. Although significant debate exists as to how much human predation and
indirect effects contributed to prehistoric extinctions, certain
population crashes have been directly correlated with human arrival. Human activity has been the main cause of mammalian extinctions since the Late Pleistocene. A 2018 study published in PNAS found that since the dawn of human civilization, the biomass
of wild mammals has decreased by 83%. The biomass decrease is 80% for
marine mammals, 50% for plants, and 15% for fish. Currently, livestock
make up 60% of the biomass of all mammals on Earth, followed by humans
(36%) and wild mammals (4%). As for birds, 70% are domesticated, such as
poultry, whereas only 30% are wild.
The percentage of megafauna on different land masses over time, with the arrival of humans indicated.
Extinction of animals, plants, and other organisms caused by human actions may go as far back as the late Pleistocene, over 12,000 years ago. There is a correlation between megafaunal extinction and the arrival of humans. Megafauna that are still extant also suffered severe declines that were highly correlated with human expansion and activity. Over the past 125,000 years, the average body size of wildlife has fallen by 14% as actions by prehistoric humans eradicated megafauna on all continents with the exception of Africa. Over the past 130,000 years, avian functional diversity has declined
precipitously and disproportionately relative to phylogenetic diversity
losses.
Human civilization was founded on and grew from agriculture. The more land used for farming, the greater the population a civilization could sustain, and subsequent popularization of farming led to widespread habitat conversion.
Habitat destruction by humans, thus replacing the original local ecosystems, is a major driver of extinction. The sustained conversion of biodiversity rich forests and wetlands into
poorer fields and pastures (of lesser carrying capacity for wild
species), over the last 10,000 years, has considerably reduced the
Earth's carrying capacity for wild birds and mammals, among other
organisms, in both population size and species count.
Recent investigations into the practice of landscape burning during the Neolithic Revolution
have a major implication for the current debate about the timing of the
Anthropocene and the role that humans may have played in the production
of greenhouse gases prior to the Industrial Revolution. Studies of early hunter-gatherers raise questions about the current use of population size or density as a proxy for the amount of land clearance and anthropogenic burning that took place in pre-industrial times.Scientists have questioned the correlation between population size and early territorial alterations. Ruddiman and Ellis' research paper in 2009 makes the case that early
farmers involved in systems of agriculture used more land per capita
than growers later in the Holocene, who intensified their labor to
produce more food per unit of area (thus, per laborer); arguing that
agricultural involvement in rice production implemented thousands of
years ago by relatively small populations created significant
environmental impacts through large-scale means of deforestation.
While a number of human-derived factors are recognized as contributing to rising atmospheric concentrations of CH4 (methane) and CO2
(carbon dioxide), deforestation and territorial clearance practices
associated with agricultural development may have contributed most to
these concentrations globally in earlier millennia. Scientists that are employing a variance of archaeological
and paleoecological data argue that the processes contributing to
substantial human modification of the environment spanned many thousands
of years on a global scale and thus, not originating as late as the Industrial Revolution. Palaeoclimatologist William Ruddiman
has argued that in the early Holocene 11,000 years ago, atmospheric
carbon dioxide and methane levels fluctuated in a pattern which was
different from the Pleistocene epoch before it. He argued that the patterns of the significant decline of CO2
levels during the last ice age of the Pleistocene inversely correlate
to the Holocene where there have been dramatic increases of CO2 around 8000 years ago and CH4 levels 3000 years after that. The correlation between the decrease of CO2 in the Pleistocene and the increase of it during the Holocene implies that the causation of this spark of greenhouse gases into the atmosphere was the growth of human agriculture during the Holocene.
Climate change
Top:Arid ice age climateMiddle:Atlantic period, warm and wetBottom: Potential vegetation in climate now if not for human effects like agriculture.
One of the main theories explaining early Holocene extinctions is historic climate change.
The climate change theory has suggested that a change in climate near
the end of the late Pleistocene stressed the megafauna to the point of
extinction. Some scientists favor abrupt climate change as the catalyst for the
extinction of the megafauna at the end of the Pleistocene, most who
believe increased hunting from early modern humans also played a part,
with others even suggesting that the two interacted. In the Americas, a controversial explanation for the shift in climate is presented under the Younger Dryas impact hypothesis, which states that the impact of comets cooled global temperatures. Despite its popularity among nonscientists, this hypothesis has never
been accepted by relevant experts, who dismiss it as a fringe theory.
There are roughly 1,000 mountain gorillas remaining. 60% of primate species face an anthropogenically driven extinction crisis and 75% have declining populations.
Contemporary human overpopulation and continued population growth, along with economic growth and per-capita consumption growth, prominently in the past two centuries, are regarded as the underlying causes of extinction. Inger Andersen, the executive director of the United Nations Environment Programme,
stated that "we need to understand that the more people there are, the
more we put the Earth under heavy pressure. As far as biodiversity is
concerned, we are at war with nature."
Some scholars assert that the emergence of capitalism as the dominant economic system has accelerated ecological exploitation and destruction, and has also exacerbated mass species extinction. CUNY professor David Harvey, for example, posits that the neoliberal era "happens to be the era of the fastest mass extinction of species in the Earth's recent history". Ecologist William E. Rees
concludes that the "neoliberal paradigm contributes significantly to
planetary unraveling" by treating the economy and the ecosphere as
totally separate systems, and by neglecting the latter. Major lobbying organizations representing corporations in the
agriculture, fisheries, forestry and paper, mining, and oil and gas
industries, including the United States Chamber of Commerce,
have been pushing back against legislation that could address the
extinction crisis. A 2022 report by the climate think tank InfluenceMap
stated that "although industry associations, especially in the US,
appear reluctant to discuss the biodiversity crisis, they are clearly
engaged on a wide range of policies with significant impacts on
biodiversity loss."
As of 2023, giraffe populations have been driven to extinction in seven countries.
The loss of animal species from ecological communities, defaunation, is primarily driven by human activity. This has resulted in empty forests, ecological communities depleted of large vertebrates. This is not to be confused with extinction, as it includes both the disappearance of species and declines in abundance. Defaunation effects were first implied at the Symposium of Plant-Animal
Interactions at the University of Campinas, Brazil in 1988 in the
context of Neotropical forests. Since then, the term has gained broader usage in conservation biology as a global phenomenon.
Big cat
populations have severely declined over the last half-century and could
face extinction in the following decades. According to 2011 IUCN estimates: lions are down to 25,000, from 450,000; leopards are down to 50,000, from 750,000; cheetahs are down to 12,000, from 45,000; tigers are down to 3,000 in the wild, from 50,000. A December 2016 study by the Zoological Society of London, Panthera Corporation and Wildlife Conservation Society
showed that cheetahs are far closer to extinction than previously
thought, with only 7,100 remaining in the wild, existing within only 9%
of their historic range. Human pressures are to blame for the cheetah population crash,
including prey loss due to overhunting by people, retaliatory killing
from farmers, habitat loss and the illegal wildlife trade. Populations of brown bears have experienced similar population decline.
The term pollinator decline
refers to the reduction in abundance of insect and other animal
pollinators in many ecosystems worldwide beginning at the end of the
twentieth century, and continuing into the present day. Pollinators, which are necessary for 75% of food crops, are declining globally in both abundance and diversity. A 2017 study led by Radboud University's
Hans de Kroon indicated that the biomass of insect life in Germany had
declined by three-quarters in the previous 25 years. Participating
researcher Dave Goulson of Sussex University
stated that their study suggested that humans are making large parts of
the planet uninhabitable for wildlife. Goulson characterized the
situation as an approaching "ecological Armageddon", adding that "if we
lose the insects then everything is going to collapse." A 2019 study found that over 40% of insect species are threatened with extinction. The most significant drivers in the decline of insect populations are associated with intensive farming practices, along with pesticide use and climate change. The world's insect population decreases by around 1 to 2% per year.
The ring-tailed lemur, one of the more than 120 unique species of mammals only found on Madagascar threatened with extinction.
We have driven the rate of
biological extinction, the permanent loss of species, up several hundred
times beyond its historical levels, and are threatened with the loss of
a majority of all species by the end of the 21st century.
Various species are predicted to become extinct in the near future, among them some species of rhinoceros, primates, and pangolins. Others, including several species of giraffe, are considered "vulnerable" and are experiencing significant population declines from anthropogenic impacts including hunting, deforestation and conflict. Hunting alone threatens bird and mammalian populations around the world. The direct killing of megafauna
for meat and body parts is the primary driver of their destruction,
with 70% of the 362 megafauna species in decline as of 2019. Mammals in particular have suffered such severe losses as the result of human activity (mainly during the Quaternary extinction event, but partly during the Holocene) that it could take several million years for them to recover. Contemporary assessments have discovered that roughly 41% of
amphibians, 25% of mammals, 21% of reptiles and 14% of birds are
threatened with extinction, which could disrupt ecosystems on a global
scale and eliminate billions of years of phylogenetic diversity. 189 countries, which are signatory to the Convention on Biological Diversity (Rio Accord), have committed to preparing a Biodiversity Action Plan, a first step at identifying specific endangered species and habitats, country by country.
For the first time since the demise
of the dinosaurs 65 million years ago, we face a global mass extinction
of wildlife. We ignore the decline of other species at our peril—for
they are the barometer that reveals our impact on the world that
sustains us.
— Mike Barrett, director of science and policy at WWF's UK branch
A 2023 study published in Current Biology concluded that current biodiversity loss rates could reach a tipping point and inevitably trigger a total ecosystem collapse.
Share of species threatened with extinction as of 2019.
Recent extinctions are more directly attributable to human
influences, whereas prehistoric extinctions can be attributed to other
factors. The International Union for Conservation of Nature (IUCN) characterizes 'recent' extinction as those that have occurred past the cut-off point of 1500, and at least 875 plant and animal species have gone extinct since that time and 2009. Some species, such as the Père David's deer and the Hawaiian crow, are extinct in the wild, and survive solely in captive populations. Other populations are only locally extinct (extirpated), still existent elsewhere, but reduced in distribution, as with the extinction of gray whales in the Atlantic, and of the leatherback sea turtle in Malaysia.
Since the Late Pleistocene, humans (together with other factors)
have been rapidly driving the largest vertebrate animals towards
extinction, and in the process interrupting a 66-million-year-old
feature of ecosystems, the relationship between diet and body mass,
which researchers suggest could have unpredictable consequences. A 2019 study published in Nature Communications
found that rapid biodiversity loss is impacting larger mammals and
birds to a much greater extent than smaller ones, with the body mass of
such animals expected to shrink by 25% over the next century. Another
2019 study published in Biology Letters found that extinction rates are perhaps much higher than previously estimated, in particular for bird species.
The 2019 Global Assessment Report on Biodiversity and Ecosystem Services
lists the primary causes of contemporary extinctions in descending
order: (1) changes in land and sea use (primarily agriculture and
overfishing respectively); (2) direct exploitation of organisms such as
hunting; (3) anthropogenic climate change; (4) pollution and (5)
invasive alien species spread by human trade. This report, along with the 2020 Living Planet Report by the WWF, both project that climate change will be the leading cause in the next several decades.
A June 2020 study published in PNAS
posits that the contemporary extinction crisis "may be the most serious
environmental threat to the persistence of civilization, because it is
irreversible" and that its acceleration "is certain because of the still
fast growth in human numbers and consumption rates." The study found
that more than 500 vertebrate species are poised to be lost in the next two decades.
The changing distribution of the world's land mammals in tonnes of carbon. The biomass of wild land mammals has declined by 85% since the emergence of humans.
Humans both create and destroy crop cultivar and domesticated animal varieties. Advances in transportation and industrial farming has led to monoculture
and the extinction of many cultivars. The use of certain plants and
animals for food has also resulted in their extinction, including silphium and the passenger pigeon. It was estimated in 2012 that 13% of Earth's ice-free land surface is
used as row-crop agricultural sites, 26% used as pastures, and 4%
urban-industrial areas.
In March 2019, Nature Climate Change published a study by ecologists from Yale University,
who found that over the next half century, human land use will reduce
the habitats of 1,700 species by up to 50%, pushing them closer to
extinction. That same month PLOS Biology published a similar study drawing on work at the University of Queensland,
which found that "more than 1,200 species globally face threats to
their survival in more than 90% of their habitat and will almost
certainly face extinction without conservation intervention".
Since 1970, the populations of migratory freshwater fish have declined by 76%, according to research published by the Zoological Society of London
in July 2020. Overall, around one in three freshwater fish species are
threatened with extinction due to human-driven habitat degradation and
overfishing.
Satellite image of rainforest converted to oil palm plantations.
Some scientists and academics assert that industrial agriculture and the growing demand for meat is contributing to significant global biodiversity loss as this is a significant driver of deforestation and habitat destruction; species-rich habitats, such as the Amazon region and Indonesia being converted to agriculture. A 2017 study by the World Wildlife Fund
(WWF) found that 60% of biodiversity loss can be attributed to the vast
scale of feed crop cultivation required to rear tens of billions of
farm animals. Moreover, a 2006 report by the Food and Agriculture Organization (FAO) of the United Nations, Livestock's Long Shadow, also found that the livestock sector is a "leading player" in biodiversity loss. More recently, in 2019, the IPBESGlobal Assessment Report on Biodiversity and Ecosystem Services
attributed much of this ecological destruction to agriculture and
fishing, with the meat and dairy industries having a very significant
impact. Since the 1970s food production has soared to feed a growing human
population and bolster economic growth, but at a huge price to the
environment and other species. The report says some 25% of the Earth's
ice-free land is used for cattle grazing. A 2020 study published in Nature Communications
warned that human impacts from housing, industrial agriculture and in
particular meat consumption are wiping out a combined 50 billion years
of Earth's evolutionary history (defined as phylogenetic diversity) and driving to extinction some of the "most unique animals on the planet," among them the Aye-aye lemur, the Chinese crocodile lizard and the pangolin. Said lead author Rikki Gumbs:
We know from all the data we have
for threatened species, that the biggest threats are agriculture
expansion and the global demand for meat. Pasture land, and the clearing
of rainforests for production of soy, for me, are the largest
drivers—and the direct consumption of animals.
Urbanization has also been cited as a significant driver of
biodiversity loss, particularly of plant life. A 1999 study of local
plant extirpations in Great Britain found that urbanization contributed
at least as much to local plant extinction as did agriculture.
Bramble Cay melomys were declared extinct in June 2016. This is the first recorded mammalian extinction due to anthropogenic climate change.
Climate change is expected to be a major driver of extinctions from the 21st century. Rising levels of carbon dioxide are resulting in influx of this gas
into the ocean, increasing its acidity. Marine organisms which possess calcium carbonate shells or exoskeletons experience physiological pressure as the carbonate reacts with acid. For example, this is already resulting in coral bleaching on various coral reefs worldwide, which provide valuable habitat and maintain a high biodiversity. Marine gastropods, bivalves, and other invertebrates are also affected, as are the organisms that feed on them. Some studies have suggested that it is not climate change that is
driving the current extinction crisis, but the demands of contemporary
human civilization on nature.However, a rise in average global temperatures greater than 5.2 °C is
projected to cause a mass extinction similar to the "Big Five" mass
extinction events of the Phanerozoic, even without other anthropogenic
impacts on biodiversity.
The vaquita,
the world's most endangered marine mammal, was reduced to 30
individuals as of February 2017. They are often killed by commercial
fishing nets. As of March 2019, only 10 remain, according to The International Committee for the Recovery of the Vaquita.The collapse of the Atlantic northwest cod fishery as a result of overfishing, and subsequent recovery.
Overhunting can reduce the local population of game animals by more than half, as well as reducing population density, and may lead to extinction for some species. Populations located nearer to villages are significantly more at risk of depletion. Several conservationist organizations, among them IFAW and HSUS, assert that trophy hunters,
particularly from the United States, are playing a significant role in
the decline of giraffes, which they refer to as a "silent extinction".
The surge in the mass killings by poachers involved in the illegal ivory trade along with habitat loss is threatening African elephant populations. In 1979, their populations stood at 1.7 million; at present there are fewer than 400,000 remaining. Prior to European colonization, scientists believe Africa was home to roughly 20 million elephants. According to the Great Elephant Census, 30% of African elephants (or 144,000 individuals) disappeared over a seven-year period, 2007 to 2014. African elephants could become extinct by 2035 if poaching rates continue.
Decline in the number of African elephants since 1500 AD
Fishing has had a devastating effect on marine organism populations
for several centuries even before the explosion of destructive and
highly effective fishing practices like trawling. Humans are unique among predators in that they regularly prey on other adult apex predators, particularly in marine environments; bluefin tuna, blue whales, North Atlantic right whales, and over fifty species of sharks and rays are vulnerable to predation pressure from human fishing, in particular commercial fishing. A 2016 study published in Science concludes that humans tend to hunt larger species, and this could disrupt ocean ecosystems for millions of years. A 2020 study published in Science Advances found that around 18% of marine megafauna, including iconic species such as the Great white shark,
are at risk of extinction from human pressures over the next century.
In a worst-case scenario, 40% could go extinct over the same time
period. According to a 2021 study published in Nature, 71% of oceanic shark and ray populations have been destroyed by overfishing (the primary driver of ocean defaunation)
from 1970 to 2018, and are nearing the "point of no return" as 24 of
the 31 species are now threatened with extinction, with several being
classified as critically endangered. Almost two-thirds of sharks and rays around coral reefs are threatened
with extinction from overfishing, with 14 of 134 species being
critically endangered.
If this pattern goes unchecked, the
future oceans would lack many of the largest species in today's oceans.
Many large species play critical roles in ecosystems and so their
extinctions could lead to ecological cascades that would influence the
structure and function of future ecosystems beyond the simple fact of
losing those species.
— Jonathan Payne, associate professor and chair of geological sciences at Stanford University
The decline of amphibian populations has also been identified as an
indicator of environmental degradation. As well as habitat loss,
introduced predators and pollution, Chytridiomycosis, a fungal infection accidentally spread by human travel, globalization, and the wildlife trade, has caused severe population
drops of over 500 amphibian species, and perhaps 90 extinctions, including (among many others) the extinction of the golden toad in Costa Rica, the Gastric-brooding frog in Australia, the Rabb's Fringe-limbed Treefrog and the extinction of the Panamanian golden frog
in the wild. Chytrid fungus has spread across Australia, New Zealand,
Central America and Africa, including countries with high amphibian
diversity such as cloud forests in Honduras and Madagascar. Batrachochytrium salamandrivorans is a similar infection currently threatening salamanders. Amphibians are now the most endangered vertebrate group, having existed for more than 300 million years through three other mass extinctions.
Millions of bats in the US have been dying off since 2012 due to a fungal infection known as white-nose syndrome
that spread from European bats, who appear to be immune. Population
drops have been as great as 90% within five years, and extinction of at
least one bat species is predicted. There is currently no form of
treatment, and such declines have been described as "unprecedented" in
bat evolutionary history by Alan Hicks of the New York State Department of Environmental Conservation.
Megafauna
were once found on every continent of the world, but are now almost
exclusively found on the continent of Africa. In some regions, megafauna
experienced population crashes and trophic cascades shortly after the earliest human settlers. Worldwide, 178 species of the world's largest mammals died out between
52,000 and 9,000 BC; it has been suggested that a higher proportion of
African megafauna survived because they evolved alongside humans. The timing of South American megafaunal extinction
appears to precede human arrival, although the possibility that human
activity at the time impacted the global climate enough to cause such an
extinction has been suggested.
Africa experienced the smallest decline in megafauna compared to the
other continents. This is presumably due to the idea that African
megafauna evolved alongside humans, and thus developed a healthy fear of
them, unlike the comparatively tame animals of other continents.
Unlike other continents, the megafauna of Eurasia went extinct over a
relatively long period of time, possibly due to climate fluctuations
fragmenting and decreasing populations, leaving them vulnerable to
over-exploitation, as with the steppe bison (Bison priscus). The warming of the arctic region caused the rapid decline of
grasslands, which had a negative effect on the grazing megafauna of
Eurasia. Most of what once was mammoth steppe was converted to mire, rendering the environment incapable of supporting them, notably the woolly mammoth. However, all these megafauna had survived previous interglacials with
the same or more intense warming, suggesting that even during warm
periods, refugia may have existed and that human hunting may have been
the critical factor for their extinction.
In the western Mediterranean region, anthropogenic forest
degradation began around 4,000 BP, during the Chalcolithic, and became
especially pronounced during the Roman era. The reasons for the decline of forest ecosystems stem from agriculture, grazing, and mining. During the twilight years of the Western Roman Empire,
forests in northwestern Europe rebounded from losses incurred
throughout the Roman period, though deforestation on a large scale
resumed once again around 800 BP, during the High Middle Ages.
In southern China, human land use is believed to have permanently
altered the trend of vegetation dynamics in the region, which was
previously governed by temperature. This is evidenced by high fluxes of
charcoal from that time interval.
Reconstructed woolly mammoth bone hut, based on finds in Mezhyrich.The passenger pigeon
was a species of pigeon endemic to North America. It experienced a
rapid decline in the late 1800s due to habitat destruction and intense
hunting by European settlers. The last wild bird is thought to have been shot in 1901.
There has been a debate as to the extent to which the disappearance of megafauna at the end of the last glacial period can be attributed to human activities by hunting, or even by slaughter of prey populations. Discoveries at Monte Verde in South America and at Meadowcroft Rock Shelter in Pennsylvania have caused a controversy regarding the Clovis culture. There likely would have been human settlements prior to the Clovis culture, and the history of humans in the Americas may extend back many thousands of years before the Clovis culture. The amount of correlation between human arrival and megafauna extinction is still being debated: for example, in Wrangel Island in Siberia the extinction of dwarf woolly mammoths (approximately 2000 BC) did not coincide with the arrival of humans, nor did megafaunal mass
extinction on the South American continent, although it has been
suggested climate changes induced by anthropogenic effects elsewhere in
the world may have contributed.
Comparisons are sometimes made between recent extinctions (approximately since the Industrial Revolution) and the Pleistocene extinction near the end of the last glacial period. The latter is exemplified by the extinction of large herbivores such as the woolly mammoth and the carnivores that preyed on them. Humans of this era actively hunted the mammoth and the mastodon, but it is not known if this hunting was the cause of the subsequent
massive ecological changes, widespread extinctions and climate changes.
The ecosystems encountered by the first Americans had not been
exposed to human interaction, and may have been far less resilient to
human made changes than the ecosystems encountered by industrial era
humans. Therefore, the actions of the Clovis people, despite seeming
insignificant by today's standards could indeed have had a profound
effect on the ecosystems and wild life which was entirely unused to
human influence.
In the Yukon, the mammoth steppe ecosystem collapsed between
13,500 and 10,000 BP, though wild horses and woolly mammoths somehow
persisted in the region for millennia after this collapse. In what is now Texas, a drop in local plant and animal biodiversity
occurred during the Younger Dryas cooling, though while plant diversity
recovered after the Younger Dryas, animal diversity did not. In the Channel Islands,
multiple terrestrial species went extinct around the same time as human
arrival, but direct evidence for an anthropogenic cause of their
extinction remains lacking. In the montane forests of the Colombian Andes, spores of coprophilous
fungi indicate megafaunal extinction occurred in two waves, the first
occurring around 22,900 BP and the second around 10,990 BP. A 2023 study of megafaunal extinctions in the Junín Plateau of Peru
found that the timing of the disappearance of megafauna was concurrent
with a large uptick in fire activity attributed to human actions,
implicating humans as the cause of their local extinction on the
plateau.
New Guinea
Humans in New Guinea used volcanically fertilised soil following
major eruptions and interfered with vegetation succession patterns since
the Late Pleistocene, with this process intensifying in the Holocene.
Australia was once home to a large assemblage of megafauna, with many parallels to those found on the African continent today. Australia's fauna is characterized by primarily marsupial mammals, and many reptiles and birds, all existing as giant forms until recently. Humans arrived on the continent very early, about 50,000 years ago. The extent human arrival contributed is controversial; climatic drying
of Australia 40,000–60,000 years ago was an unlikely cause, as it was
less severe in speed or magnitude than previous regional climate change
which failed to kill off megafauna. Extinctions in Australia continued
from original settlement until today in both plants and animals, while many more animals and plants have declined or are endangered.
Due to the older timeframe and the soil chemistry on the continent, very little subfossil preservation evidence exists relative to elsewhere. However, continent-wide extinction of all genera weighing over 100
kilograms, and six of seven genera weighing between 45 and 100 kilograms
occurred around 46,400 years ago and the fact that megafauna survived until a later date on the island of Tasmania following the establishment of a land bridge suggest direct hunting or anthropogenic ecosystem disruption such as fire-stick farming as likely causes. The first evidence of direct human predation leading to extinction in Australia was published in 2016.
A 2021 study found that the rate of extinction of Australia's
megafauna is rather unusual, with some generalistic species having gone
extinct earlier while highly specialized ones having become extinct
later or even still surviving today. A mosaic cause of extinction with
different anthropogenic and environmental pressures has been proposed.
The arrival of invasive species such as feral cats and cane toads has further devastated Australia's ecosystems.
Since European colonisation Australia has lost over 100 plant and
animal species, including 10% of its mammal species, the highest of any
continent.
Caribbean
Recently extinct flightless birds include Madagascar's elephant bird (left), Mauritius's dodo and the great auk of the Atlantic (bottom right).
Human arrival in the Caribbean around 6,000 years ago is correlated with the extinction of many species. These include many different genera of ground and arboreal sloths across all islands. These sloths were generally smaller than those found on the South American continent. Megalocnus were the largest genus at up to 90 kilograms (200 lb), Acratocnus were medium-sized relatives of modern two-toed sloths endemic to Cuba, Imagocnus also of Cuba, Neocnus and many others.
Macaronesia
The arrival of the first human settlers in the Azores
saw the introduction of invasive plants and livestock to the
archipelago, resulting in the extinction of at least two plant species
on Pico Island. On Faial Island, the decline of Prunus lusitanica
has been hypothesized by some scholars to have been related to the tree
species being endozoochoric, with the extirpation or extinction of
various bird species drastically limiting its seed dispersal. Lacustrine ecosystems were ravaged by human colonization, as evidenced by hydrogen isotopes from C30 fatty acids recording hypoxic bottom waters caused by eutrophication in Lake Funda on Flores Island beginning between 1500 and 1600 AD.
The arrival of humans on the archipelago of Madeira
caused the extinction of approximately two-thirds of its endemic bird
species, with two non-endemic birds also being locally extirpated from
the archipelago. Of thirty-four land snail species collected in a subfossil sample from eastern Madeira Island, nine became extinct following the arrival of humans. On the Desertas Islands,
of forty-five land snail species known to exist before human
colonization, eighteen are extinct and five are no longer present on the
islands. Eurya stigmosa,
whose extinction is typically attributed to climate change following
the end of the Pleistocene rather than humans, may have survived until
the colonization of the archipelago by the Portuguese and gone extinct
as a result of human activity. Introduced mice have been implicated as a leading driver of extinction
on Madeira following its discovery and settlement by humans.
In the Canary Islands,
native thermophilous woodlands were decimated and two tree taxa were
driven extinct following the arrival of its first humans, primarily as a
result of increased fire clearance and soil erosion and the
introduction of invasive pigs, goats, and rats. Invasive species
introductions accelerated during the Age of Discovery when Europeans first settled the Macaronesian
archipelago. The archipelago's laurel forests, though still negatively
impacted, fared better due to being less suitable for human economic
use.
Cabo Verde,
like the Canary Islands, witnessed precipitous deforestation upon the
arrival of European settlers and various invasive species brought by
them in the archipelago, with the archipelago's thermophilous woodlands suffering the greatest destruction. Introduced species, overgrazing, increased fire incidence, and soil
degradation have been attributed as the chief causes of Cabo Verde's
ecological devastation.
Pacific
Archaeological and paleontological digs on 70 different Pacific islands suggested that numerous species became extinct as people moved across the Pacific, starting 30,000 years ago in the Bismarck Archipelago and Solomon Islands. It is currently estimated that among the bird species of the Pacific,
some 2000 species have gone extinct since the arrival of humans,
representing a 20% drop in the biodiversity of birds worldwide. In Polynesia, the Late Holocene declines in avifaunas only abated after
they were heavily depleted and there were increasingly fewer bird
species able to be driven to extinction. Iguanas were likewise decimated by the spread of humans. Additionally, the endemic faunas of Pacific archipelagos are
exceptionally at risk in the coming decades due to rising sea levels
caused by global warming.
Lord Howe Island, which remained uninhabited until the arrival of
Europeans in the South Pacific in the 18th century, lost much of its
endemic avifauna when it became a whaling station in the early 19th
century. Another wave of bird extinctions occurred following the
introduction of black rats in 1918.
The endemic megafaunal meiolaniid turtles of Vanuatu -
representing the final members of a group that had existed for over 100
million years - became extinct immediately following the first human
arrivals and remains of them containing evidence of butchery by humans
have been found.
The arrival of humans in New Caledonia marked the commencement of coastal forest and mangrove decline on the island. The archipelago's megafauna - such as the large, flightless galliformSylviornis - was still extant when humans arrived, but indisputable evidence for the anthropogenicity of their extinction remains elusive.
In Fiji, the giant iguanas Brachylophus gibbonsi and Lapitiguana impensa both succumbed to human-induced extinction shortly after encountering the first humans on the island.
In American Samoa,
deposits dating back to the period of initial human colonisation
contain elevated quantities of bird, turtle, and fish remains caused by
increased predation pressure.
On Mangaia in the Cook Islands, human colonisation was associated with a major extinction of endemic avifauna, along with deforestation, erosion of volcanic hillsides, and increased
charcoal influx, causing additional environmental damage.
On Rapa in the Austral Archipelago, human arrival, marked by the increase in charcoal and in taro pollen in the palynological record, is associated with the extinction of an endemic palm.
Henderson Island, once thought to be untouched by humans, was
colonised and later abandoned by Polynesians. The ecological collapse on
the island caused by the anthropogenic extinctions is believed to have
caused the island's abandonment.
The first human settlers of the Hawaiian Islands are thought to have arrived between 300 and 800 AD, with European arrival in the 16th century. Hawaii is notable for its endemism of plants, birds, insects, mollusks and fish;
30% of its organisms are endemic. Many of its species are endangered or
have gone extinct, primarily due to accidentally introduced species and
livestock grazing. Over 40% of its bird species have gone extinct, and
it is the location of 75% of extinctions in the United States. Evidence suggests that the introduction of the Polynesian rat, above
all other factors, drove the ecocide of the endemic forests of the
archipelago. Extinction has increased in Hawaii over the last 200 years and is
relatively well documented, with extinctions among native snails used as
estimates for global extinction rates. High rates of habitat fragmentation on the archipelago have further reduced biodiversity. The extinction of endemic Hawaiian avifauna is likely to accelerate
even further as anthropogenic global warming adds additional pressure on
top of land-use changes and invasive species.
Radiocarbon dating of multiple subfossil specimens shows that now extinct giant lemurs were present in Madagascar until after human arrival.
Within centuries of the arrival of humans around the 1st millennium AD, nearly all of Madagascar's distinct, endemic, and geographically isolated megafauna became extinct. The largest animals, of more than 150 kilograms (330 lb), were extinct
very shortly after the first human arrival, with large and medium-sized
species dying out after prolonged hunting pressure from an expanding
human population moving into more remote regions of the island around
1000 years ago. as well as 17 species of "giant" lemurs.
Some of these lemurs typically weighed over 150 kilograms (330 lb), and
their fossils have provided evidence of human butchery on many species. Other megafauna present on the island included the Malagasy hippopotamuses as well as the large flightless elephant birds, both groups are thought to have gone extinct in the interval 750–1050 AD. Smaller fauna experienced initial increases due to decreased competition, and then subsequent declines over the last 500 years. All fauna weighing over 10 kilograms (22 lb) died out. The primary
reasons for the decline of Madagascar's biota, which at the time was
already stressed by natural aridification, were human hunting, herding,farming, and forest clearing, all of which persist and threaten Madagascar's remaining taxa today.
The natural ecosystems of Madagascar as a whole were further impacted by
the much greater incidence of fire as a result of anthropogenic fire
production; evidence from Lake Amparihibe on the island of Nosy Be
indicates a shift in local vegetation from intact rainforest to a
fire-disturbed patchwork of grassland and woodland between 1300 and 1000
BP.
New Zealand is characterized by its geographic isolation and island biogeography,
and had been isolated from mainland Australia for 80 million years. It
was the last large land mass to be colonized by humans. Upon the arrival
of Polynesian
settlers in the late 13th century, the native biota suffered a
catastrophic decline due to deforestation, hunting, and the introduction
of invasive species.The extinction of all of the islands' megafaunal birds occurred within several hundred years of human arrival. The moa, large flightless ratites, were thriving during the Late Holocene, but became extinct within 200 years of the arrival of human settlers, as did the enormous Haast's eagle - their primary predator - the omnivorous adzebills and at least two species of large, flightless geese. The Polynesians also introduced the Polynesian rat,
which may have consumed avian eggs and chicks. This may have put some
pressure on other birds, but at the time of early European contact (18th
century) and colonization (19th century), the bird life was nonetheless
prolific. The megafaunal extinction happened extremely rapidly despite a very
small population density, which never exceeded 0.01 people per km2. Extinctions of parasites followed the extinction of New Zealand's megafauna. With them, the Europeans brought various invasive species including ship rats, possums, cats and mustelids which devastated native bird life, some of which had adapted flightlessness and ground nesting habits, and had no defensive behavior as a result of having no native mammalian predators. The kākāpō,
the world's biggest parrot, which is flightless, now only exists in
managed breeding sanctuaries. New Zealand's national emblem, the kiwi, is on the endangered bird list.
Stabilizing human populations; reining in capitalism, decreasing economic demands, and shifting them to economic activities with low impacts on biodiversity; transitioning to plant-based diets; and increasing the number and size of terrestrial and marine protected areas have been suggested to avoid or limit biodiversity loss and a possible sixth mass extinction. Rodolfo Dirzo and Paul R. Ehrlich suggest that "the one fundamental, necessary, 'simple' cure, ... is reducing the scale of the human enterprise.[ According to a 2021 paper published in Frontiers in Conservation Science,
humanity almost certainly faces a "ghastly future" of mass extinction,
biodiversity collapse, climate change, and their impacts unless major
efforts to change human industry and activity are rapidly undertaken.
A 2018 article in Science advocated for the global community to designate 30% of the planet by 2030, and 50% by 2050, as protected areas to mitigate the contemporary extinction crisis. It highlighted that the human population is projected to grow to 10 billion by the middle of the century, and consumption of food and water resources is projected to double by this time. A 2022 report published in Science
warned that 44% of Earth's terrestrial surface, or 64 million square
kilometres (24.7 million square miles), must be conserved and made
"ecologically sound" to prevent further biodiversity loss.
In November 2018, the UN's biodiversity chief Cristiana Pașca Palmer
urged people worldwide to pressure governments to implement significant
protections for wildlife by 2020. She called biodiversity loss a
"silent killer" as dangerous as global warming
but said it had received little attention by comparison. "It's
different from climate change, where people feel the impact in everyday
life. With biodiversity, it is not so clear but by the time you feel
what is happening, it may be too late." In January 2020, the UN Convention on Biological Diversity drafted a Paris-style plan to stop biodiversity and ecosystem collapse by setting the deadline of 2030 to protect 30% of the Earth's land and oceans and to reduce pollution by 50%, to allow for the restoration of ecosystems by 2050. The world failed to meet the Aichi Biodiversity Targets for 2020 set by the convention during a summit in Japan in 2010. Of the 20 biodiversity targets proposed, only six were "partially achieved" by the deadline. It was called a global failure by Inger Andersen, head of the United Nations Environment Programme:
From COVID-19 to massive wildfires, floods, melting glaciers and unprecedented heat, our failure to meet the Aichi (biodiversity) targets—to protect our home—has very real consequences. We can no longer afford to cast nature to the side.
Some scientists have proposed keeping extinctions below 20 per year
for the next century as a global target to reduce species loss, which is
the biodiversity equivalent of the 2 °C climate target, although it is
still much higher than the normal background rate of two per year prior
to anthropogenic impacts on the natural world.
An October 2020 report on the "era of pandemics" from IPBES found that many of the same human activities that contribute to biodiversity loss and climate change, including deforestation and the wildlife trade, have also increased the risk of future pandemics.
The report offers several policy options to reduce such risk, such as
taxing meat production and consumption, cracking down on the illegal
wildlife trade, removing high disease-risk species from the legal
wildlife trade, and eliminating subsidies to businesses which are
harmful to the environment. According to marine zoologist John Spicer, "the COVID-19 crisis
is not just another crisis alongside the biodiversity crisis and the
climate change crisis. Make no mistake, this is one big crisis—the
greatest that humans have ever faced."
In December 2022, nearly every country on Earth, with the United States and the Holy See being the only exceptions, signed onto the Kunming-Montreal Global Biodiversity Framework agreement formulated at the 2022 United Nations Biodiversity Conference
(COP 15) which includes protecting 30% of land and oceans by 2030 and
22 other targets intended to mitigate the extinction crisis. The
agreement is weaker than the Aichi Targets of 2010. It was criticized by some countries for being rushed and not going far enough to protect endangered species.
Reducing human population growth has been suggested as a means of mitigating climate change and the biodiversity crisis, although many scholars believe it has been largely ignored in mainstream policy discourse. An alternative proposal is greater agricultural efficiency & sustainability. Lots of non-arable land can be made into arable land good for growing food crops. Mushrooms have also been known to repair damaged soil.
.jpg)
_(14576727409).jpg)
.jpg)
.JPG)
.jpg)
.jpg)
