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Concept: Megafauna



Concepts: Megafauna, Green turtle, Georges Cuvier, Mammoth, Woolly mammoth, Wrangel Island, Pleistocene mammals, Pleistocene megafauna





Megaherbivores (>1000 kg) are critical for ecosystem health and function, but face population collapse and extinction globally. The future of these megaherbivore-impoverished ecosystems is difficult to predict, though many studies have demonstrated increasing representation of C3 woody plants. These studies rely on direct observational data, however, and tools for assessing decadal-scale changes in African ecology without observation are lacking. We use isotopic records of historical common hippopotamus (Hippopotamus amphibius) canines to quantify herbaceous vegetation change in Queen Elizabeth National Park, Uganda following a period of civil unrest and poaching. This poaching event led to population collapse of two threatened African megaherbivore species: hippopotamus and African elephants (Loxodonta africana). Serial carbon isotope ratios (δ(13)C) in canine enamel from individuals that lived between 1960-2000 indicated substantial increases in C3 herbaceous plants in their diet (<20% C3 in the 1960s to 30-45% C3 in the 80s and 90s), supported by other observational and ecological data. These data indicate megaherbivore loss results in succession of both woody and herbaceous C3 vegetation and further reaching effects, such as decreased grazing capacity and herbivore biodiversity in the area. Given multiple lines of evidence, these individuals appear to accurately capture herbaceous vegetation change in Mweya.

Concepts: Ecology, Elephant, Hippopotamus, Perennial plant, Megafauna, Herbaceous plant


Extinctions can dramatically reshape biological communities. As a case in point, ancient mass extinction events apparently facilitated dramatic new evolutionary radiations of surviving lineages. However, scientists have yet to fully understand the consequences of more recent biological upheaval, such as the megafaunal extinctions that occurred globally over the past 50 kyr. New Zealand was the world’s last large landmass to be colonized by humans, and its exceptional archaeological record documents a vast number of vertebrate extinctions in the immediate aftermath of Polynesian arrival approximately AD 1280. This recently colonized archipelago thus presents an outstanding opportunity to test for rapid biological responses to extinction. Here, we use ancient DNA (aDNA) analysis to show that extinction of an endemic sea lion lineage (Phocarctos spp.) apparently facilitated a subsequent northward range expansion of a previously subantarctic-limited lineage. This finding parallels a similar extinction-replacement event in penguins (Megadyptes spp.). In both cases, an endemic mainland clade was completely eliminated soon after human arrival, and then replaced by a genetically divergent clade from the remote subantarctic region, all within the space of a few centuries. These data suggest that ecological and demographic processes can play a role in constraining lineage distributions, even for highly dispersive species, and highlight the potential for dynamic biological responses to extinction.

Concepts: Evolution, Biology, Ecology, Extinction, Dinosaur, Megafauna, Extinction event, Timeline of extinctions



Concepts: Human, Africa, Thought, Neanderthal, Human evolution, Prehistory, Megafauna, Homo sapiens idaltu


The late Quaternary megafauna extinction was a severe global-scale event. Two factors, climate change and modern humans, have received broad support as the primary drivers, but their absolute and relative importance remains controversial. To date, focus has been on the extinction chronology of individual or small groups of species, specific geographical regions or macroscale studies at very coarse geographical and taxonomic resolution, limiting the possibility of adequately testing the proposed hypotheses. We present, to our knowledge, the first global analysis of this extinction based on comprehensive country-level data on the geographical distribution of all large mammal species (more than or equal to 10 kg) that have gone globally or continentally extinct between the beginning of the Last Interglacial at 132,000 years BP and the late Holocene 1000 years BP, testing the relative roles played by glacial-interglacial climate change and humans. We show that the severity of extinction is strongly tied to hominin palaeobiogeography, with at most a weak, Eurasia-specific link to climate change. This first species-level macroscale analysis at relatively high geographical resolution provides strong support for modern humans as the primary driver of the worldwide megafauna losses during the late Quaternary.

Concepts: Human, Species, Mammal, Extinction, Pleistocene, Holocene, Megafauna, Holocene extinction



Concepts: Horse, Extinction, Pleistocene, Equus, Donkey, Megafauna, Mammoth, Holocene extinction


The hominin record from southern Asia for the early Late Pleistocene epoch is scarce. Well-dated and well-preserved fossils older than ∼45,000 years that can be unequivocally attributed to Homo sapiens are lacking. Here we present evidence from the newly excavated Fuyan Cave in Daoxian (southern China). This site has provided 47 human teeth dated to more than 80,000 years old, and with an inferred maximum age of 120,000 years. The morphological and metric assessment of this sample supports its unequivocal assignment to H. sapiens. The Daoxian sample is more derived than any other anatomically modern humans, resembling middle-to-late Late Pleistocene specimens and even contemporary humans. Our study shows that fully modern morphologies were present in southern China 30,000-70,000 years earlier than in the Levant and Europe. Our data fill a chronological and geographical gap that is relevant for understanding when H. sapiens first appeared in southern Asia. The Daoxian teeth also support the hypothesis that during the same period, southern China was inhabited by more derived populations than central and northern China. This evidence is important for the study of dispersal routes of modern humans. Finally, our results are relevant to exploring the reasons for the relatively late entry of H. sapiens into Europe. Some studies have investigated how the competition with H. sapiens may have caused Neanderthals' extinction (see ref. 8 and references therein). Notably, although fully modern humans were already present in southern China at least as early as ∼80,000 years ago, there is no evidence that they entered Europe before ∼45,000 years ago. This could indicate that H. neanderthalensis was indeed an additional ecological barrier for modern humans, who could only enter Europe when the demise of Neanderthals had already started.

Concepts: Human, Neanderthal, Human evolution, Pleistocene, Megafauna, Humans, Homo sapiens idaltu, Late Pleistocene


The time of arrival of people in Australia is an unresolved question. It is relevant to debates about when modern humans first dispersed out of Africa and when their descendants incorporated genetic material from Neanderthals, Denisovans and possibly other hominins. Humans have also been implicated in the extinction of Australia’s megafauna. Here we report the results of new excavations conducted at Madjedbebe, a rock shelter in northern Australia. Artefacts in primary depositional context are concentrated in three dense bands, with the stratigraphic integrity of the deposit demonstrated by artefact refits and by optical dating and other analyses of the sediments. Human occupation began around 65,000 years ago, with a distinctive stone tool assemblage including grinding stones, ground ochres, reflective additives and ground-edge hatchet heads. This evidence sets a new minimum age for the arrival of humans in Australia, the dispersal of modern humans out of Africa, and the subsequent interactions of modern humans with Neanderthals and Denisovans.

Concepts: Human, Africa, Hominidae, Neanderthal, Human evolution, Pleistocene, Megafauna, Homininae



Concepts: Species, Ecology, Oceanography, Statistical significance, Relative humidity, Estimation, Region, Megafauna