Gronk
2024-07-02 18:46:57 UTC
https://www.eurekalert.org/news-releases/1049981
The debate has raged for decades: Was it
humans or climate change that led to the
extinction of many species of large mammals,
birds, and reptiles that have disappeared
from Earth over the past 50,000 years?
By "large," we mean animals that weighed
at least 45 kilograms – known as megafauna.
At least 161 species of mammals were driven
to extinction during this period. This number
is based on the remains found so far.
The largest of them were hit the hardest –
land-dwelling herbivores weighing over a ton,
the megaherbivores. Fifty thousand years ago,
there were 57 species of megaherbivores.
Today, only 11 remain. These remaining 11
species have also seen drastic declines in
their populations, but not to the point of
complete extinction.
A research group from the Danish National
Research Foundation's Center for Ecological
Dynamics in a Novel Biosphere (ECONOVO) at
Aarhus University now concludes that many
of these vanished species were hunted to
extinction by humans.
...
https://www.cambridge.org/core/journals/cambridge-prisms-extinction/article/latequaternary-megafauna-extinctions-patterns-causes-ecological-consequences-and-implications-for-ecosystem-management-in-the-anthropocene/E885D8C5C90424254C1C75A61DE9D087
The late-Quaternary megafauna extinctions:
Patterns, causes, ecological consequences
and implications for ecosystem management
in the Anthropocene
Abstract
Across the last ~50,000 years (the late
Quaternary) terrestrial vertebrate faunas
have experienced severe losses of large
species (megafauna), with most extinctions
occurring in the Late Pleistocene and Early
to Middle Holocene. Debate on the causes
has been ongoing for over 200 years,
intensifying from the 1960s onward. Here,
we outline criteria that any causal
hypothesis needs to account for.
Importantly, this extinction event is
unique relative to other Cenozoic (the last
66 million years) extinctions in its strong
size bias. For example, only 11 out of 57
species of megaherbivores (body mass ≥1,000
kg) survived to the present. In addition to
mammalian megafauna, certain other groups
also experienced substantial extinctions,
mainly large non-mammalian vertebrates and
smaller but megafauna-associated taxa.
Further, extinction severity and dates
varied among continents, but severely
affected all biomes, from the Arctic to the
tropics. We synthesise the evidence for and
against climatic or modern human (Homo
sapiens) causation, the only existing tenable
hypotheses. Our review shows that there is
little support for any major influence of
climate, neither in global extinction
patterns nor in fine-scale spatiotemporal
and mechanistic evidence. Conversely, there
is strong and increasing support for human
pressures as the key driver of these
extinctions, with emerging evidence for an
initial onset linked to pre-sapiens hominins
prior to the Late Pleistocene. Subsequently,
we synthesize the evidence for ecosystem
consequences of megafauna extinctions and
discuss the implications for conservation
and restoration. A broad range of evidence
indicates that the megafauna extinctions
have elicited profound changes to ecosystem
structure and functioning. The
late-Quaternary megafauna extinctions
thereby represent an early, large-scale
human-driven environmental transformation,
constituting a progenitor of the Anthropocene,
where humans are now a major player in
planetary functioning. Finally, we conclude
that megafauna restoration via trophic
rewilding can be expected to have positive
effects on biodiversity across varied
Anthropocene settings.
The debate has raged for decades: Was it
humans or climate change that led to the
extinction of many species of large mammals,
birds, and reptiles that have disappeared
from Earth over the past 50,000 years?
By "large," we mean animals that weighed
at least 45 kilograms – known as megafauna.
At least 161 species of mammals were driven
to extinction during this period. This number
is based on the remains found so far.
The largest of them were hit the hardest –
land-dwelling herbivores weighing over a ton,
the megaherbivores. Fifty thousand years ago,
there were 57 species of megaherbivores.
Today, only 11 remain. These remaining 11
species have also seen drastic declines in
their populations, but not to the point of
complete extinction.
A research group from the Danish National
Research Foundation's Center for Ecological
Dynamics in a Novel Biosphere (ECONOVO) at
Aarhus University now concludes that many
of these vanished species were hunted to
extinction by humans.
...
https://www.cambridge.org/core/journals/cambridge-prisms-extinction/article/latequaternary-megafauna-extinctions-patterns-causes-ecological-consequences-and-implications-for-ecosystem-management-in-the-anthropocene/E885D8C5C90424254C1C75A61DE9D087
The late-Quaternary megafauna extinctions:
Patterns, causes, ecological consequences
and implications for ecosystem management
in the Anthropocene
Abstract
Across the last ~50,000 years (the late
Quaternary) terrestrial vertebrate faunas
have experienced severe losses of large
species (megafauna), with most extinctions
occurring in the Late Pleistocene and Early
to Middle Holocene. Debate on the causes
has been ongoing for over 200 years,
intensifying from the 1960s onward. Here,
we outline criteria that any causal
hypothesis needs to account for.
Importantly, this extinction event is
unique relative to other Cenozoic (the last
66 million years) extinctions in its strong
size bias. For example, only 11 out of 57
species of megaherbivores (body mass ≥1,000
kg) survived to the present. In addition to
mammalian megafauna, certain other groups
also experienced substantial extinctions,
mainly large non-mammalian vertebrates and
smaller but megafauna-associated taxa.
Further, extinction severity and dates
varied among continents, but severely
affected all biomes, from the Arctic to the
tropics. We synthesise the evidence for and
against climatic or modern human (Homo
sapiens) causation, the only existing tenable
hypotheses. Our review shows that there is
little support for any major influence of
climate, neither in global extinction
patterns nor in fine-scale spatiotemporal
and mechanistic evidence. Conversely, there
is strong and increasing support for human
pressures as the key driver of these
extinctions, with emerging evidence for an
initial onset linked to pre-sapiens hominins
prior to the Late Pleistocene. Subsequently,
we synthesize the evidence for ecosystem
consequences of megafauna extinctions and
discuss the implications for conservation
and restoration. A broad range of evidence
indicates that the megafauna extinctions
have elicited profound changes to ecosystem
structure and functioning. The
late-Quaternary megafauna extinctions
thereby represent an early, large-scale
human-driven environmental transformation,
constituting a progenitor of the Anthropocene,
where humans are now a major player in
planetary functioning. Finally, we conclude
that megafauna restoration via trophic
rewilding can be expected to have positive
effects on biodiversity across varied
Anthropocene settings.