Human arrival scenarios have a strong influence on interpretations of the late Quaternary extinctions

Until recently in Earth history, very large herbivores (mammoths, ground sloths, diprotodons, and many others) occurred in most of the World’s terrestrial ecosystems, but the majority have gone extinct as part of the late-Quaternary extinctions. How has this large-scale removal of large herbivores affected landscape structure and ecosystem functioning? In this review, we combine paleo-data with information from modern exclosure experiments to assess the impact of large herbivores (and their disappearance) on woody species, landscape structure, and ecosystem functions. In modern landscapes characterized by intense herbivory, woody plants can persist by defending themselves or by association with defended species, can persist by growing in places that are physically inaccessible to herbivores, or can persist where high predator activity limits foraging by herbivores. At the landscape scale, different herbivore densities and assemblages may result in dynamic gradients in woody cover. The late-Quaternary extinctions were natural experiments in large-herbivore removal; the paleoecological record shows evidence of widespread changes in community composition and ecosystem structure and function, consistent with modern exclosure experiments. We propose a conceptual framework that describes the impact of large herbivores on woody plant abundance mediated by herbivore diversity and density, predicting that herbivore suppression of woody plants is strongest where herbivore diversity is high. We conclude that the decline of large herbivores induces major alterations in landscape structure and ecosystem functions.

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Exaptation Traits for Megafaunal Mutualisms as a Factor in Plant Domestication

Frontiers in Plant Science ◽

10.3389/fpls.2021.649394 ◽

2021 ◽

Vol 12 ◽

Author(s):

Robert N. Spengler ◽

Michael Petraglia ◽

Patrick Roberts ◽

Kseniia Ashastina ◽

Logan Kistler ◽

...

Keyword(s):

Population Dynamics ◽

Seed Dispersal ◽

Late Quaternary ◽

Plant Domestication ◽

Woody Vegetation ◽

High Plasticity ◽

Selective Pressures ◽

Investment In Reproduction ◽

Self Compatibility ◽

Quaternary Extinctions

Megafaunal extinctions are recurring events that cause evolutionary ripples, as cascades of secondary extinctions and shifting selective pressures reshape ecosystems. Megafaunal browsers and grazers are major ecosystem engineers, they: keep woody vegetation suppressed; are nitrogen cyclers; and serve as seed dispersers. Most angiosperms possess sets of physiological traits that allow for the fixation of mutualisms with megafauna; some of these traits appear to serve as exaptation (preadaptation) features for farming. As an easily recognized example, fleshy fruits are, an exaptation to agriculture, as they evolved to recruit a non-human disperser. We hypothesize that the traits of rapid annual growth, self-compatibility, heavy investment in reproduction, high plasticity (wide reaction norms), and rapid evolvability were part of an adaptive syndrome for megafaunal seed dispersal. We review the evolutionary importance that megafauna had for crop and weed progenitors and discuss possible ramifications of their extinction on: (1) seed dispersal; (2) population dynamics; and (3) habitat loss. Humans replaced some of the ecological services that had been lost as a result of late Quaternary extinctions and drove rapid evolutionary change resulting in domestication.

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Faculty Opinions recommendation of Climate predictors of late quaternary extinctions.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.5526956.5490070 ◽

2010 ◽

Author(s):

Roland Jansson

Keyword(s):

Late Quaternary ◽

Quaternary Extinctions

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North American Late Quaternary Extinctions and the Radiocarbon Record

10.2307/j.ctv264f91j.26 ◽

2022 ◽

pp. 440-450

Author(s):

JIM I. MEAD ◽

DAVID J. MELTZER

Keyword(s):

North American ◽

Late Quaternary ◽

Quaternary Extinctions

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Pre-Wisconsinan Mammals from Jamaica and Models of Late Quaternary Extinction in the Greater Antilles

Quaternary Research ◽

10.1016/0033-5894(89)90088-4 ◽

1989 ◽

Vol 31 (1) ◽

pp. 94-106 ◽

Cited By ~ 33

Author(s):

R. D. E. MacPhee ◽

Derek C. Ford ◽

Donald A. McFarlane

Keyword(s):

West Indies ◽

Late Quaternary ◽

Greater Antilles ◽

Annual Review ◽

Local Fauna ◽

The West ◽

Terrestrial Vertebrate ◽

Spin Resonance ◽

The Caribbean ◽

Quaternary Extinctions

AbstractThe vertebrate fauna recovered from indurated conglomerates at Wallingford Roadside Cave (central Jamaica) is shown to be in excess of 100,000 yr old according to uranium series and electron spin resonance dating. The Wallingford local fauna is therefore pre-Wisconsinan in age, and Roadside Cave is now the oldest radiometrically dated locality in the West Indies containing identifiable species of land mammals. In the absence of a good radiometric record for Quaternary paleontological sites in the Caribbean, there is no satisfactory basis for determining whether most extinct Antillean mammals died out in a “blitzkrieg”-like event immediately following initial human colonization in the mid-Holocene. Fossils of Clidomys (Heptaxodontidae, Caviomorpha), the giant Wallingford rodent, have never been found in situ in sediments of demonstrably Holocene age, and its extinction may antedate the middle Holocene. This is also a possibility for the primate Xenothrix mcgregori, although its remains have been found in loose cave earth. A major, climate-driven bout of terrestrial vertebrate extinction at about 14,000–12,000 yr B.P. has been hypothesized for the West Indies by G. Pregill and S. L. Olson (Annual Review of Ecology and Systematics 12, 75–98, 1981), but at present there is nothing to connect the disappearance of Clidomys with this event either. Quaternary extinctions in the Caribbean may prove to be of critical significance for evaluating the reality of New World blitzkrieg, but not until an effort is mounted to constrain them rigorously using modern radiometric approaches.

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Mammals (Late Quaternary), Extinctions of

Encyclopedia of Biodiversity ◽

10.1016/b978-0-12-384719-5.00090-3 ◽

2001 ◽

pp. 721-732

Author(s):

Paul S. Martin

Keyword(s):

Late Quaternary ◽

Quaternary Extinctions

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Micro Methods for Megafauna: Novel Approaches to Late Quaternary Extinctions and Their Contributions to Faunal Conservation in the Anthropocene

BioScience ◽

10.1093/biosci/biz105 ◽

2019 ◽

Vol 69 (11) ◽

pp. 877-887

Author(s):

Jillian A Swift ◽

Michael Bunce ◽

Joe Dortch ◽

Kristina Douglass ◽

J Tyler Faith ◽

...

Keyword(s):

Climate Change ◽

Homo Sapiens ◽

Late Quaternary ◽

Isotope Analysis ◽

Global Solutions ◽

Local Context ◽

Data Sets ◽

Recent Developments ◽

Context Specific ◽

Quaternary Extinctions

Abstract Drivers of Late Quaternary megafaunal extinctions are relevant to modern conservation policy in a world of growing human population density, climate change, and faunal decline. Traditional debates tend toward global solutions, blaming either dramatic climate change or dispersals of Homo sapiens to new regions. Inherent limitations to archaeological and paleontological data sets often require reliance on scant, poorly resolved lines of evidence. However, recent developments in scientific technologies allow for more local, context-specific approaches. In the present article, we highlight how developments in five such methodologies (radiocarbon approaches, stable isotope analysis, ancient DNA, ancient proteomics, microscopy) have helped drive detailed analysis of specific megafaunal species, their particular ecological settings, and responses to new competitors or predators, climate change, and other external phenomena. The detailed case studies of faunal community composition, extinction chronologies, and demographic trends enabled by these methods examine megafaunal extinctions at scales appropriate for practical understanding of threats against particular species in their habitats today.

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