The earliest hominin occupation of Europe is one of the most debated topics in palaeoanthropology. However, the purportedly oldest of the Early Pleistocene sites in Eurasia lack precise age control and contain stone tools rather than human fossil remains. Here we report the discovery of a human mandible associated with an assemblage of Mode 1 lithic tools and faunal remains bearing traces of hominin processing, in stratigraphic level TE9 at the site of the Sima del Elefante, Atapuerca, Spain. Level TE9 has been dated to the Early Pleistocene (approximately 1.2-1.1 Myr), based on a combination of palaeomagnetism, cosmogenic nuclides and biostratigraphy. The Sima del Elefante site thus emerges as the oldest, most accurately dated record of human occupation in Europe, to our knowledge. The study of the human mandible suggests that the first settlement of Western Europe could be related to an early demographic expansion out of Africa. The new evidence, with previous findings in other Atapuerca sites (level TD6 from Gran Dolina), also suggests that a speciation event occurred in this extreme area of the Eurasian continent during the Early Pleistocene, initiating the hominin lineage represented by the TE9 and TD6 hominins.

Woolly mammoths inhabited Eurasia and North America from late Middle Pleistocene (300 ky BP [300,000 years before present]), surviving through different climatic cycles until they vanished in the Holocene (3.6 ky BP). The debate about why the Late Quaternary extinctions occurred has centred upon environmental and human-induced effects, or a combination of both. However, testing these two hypotheses—climatic and anthropogenic—has been hampered by the difficulty of generating quantitative estimates of the relationship between the contraction of the mammoth's geographical range and each of the two hypotheses. We combined climate envelope models and a population model with explicit treatment of woolly mammoth–human interactions to measure the extent to which a combination of climate changes and increased human pressures might have led to the extinction of the species in Eurasia. Climate conditions for woolly mammoths were measured across different time periods: 126 ky BP, 42 ky BP, 30 ky BP, 21 ky BP, and 6 ky BP. We show that suitable climate conditions for the mammoth reduced drastically between the Late Pleistocene and the Holocene, and 90% of its geographical range disappeared between 42 ky BP and 6 ky BP, with the remaining suitable areas in the mid-Holocene being mainly restricted to Arctic Siberia, which is where the latest records of woolly mammoths in continental Asia have been found. Results of the population models also show that the collapse of the climatic niche of the mammoth caused a significant drop in their population size, making woolly mammoths more vulnerable to the increasing hunting pressure from human populations. The coincidence of the disappearance of climatically suitable areas for woolly mammoths and the increase in anthropogenic impacts in the Holocene, the coup de grâce, likely set the place and time for the extinction of the woolly mammoth.

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Aim  Variation in species richness has been related to (1) environmental conditions (water, energy and habitat characteristics) and (2) regional differences (contingent historical events and regional particularities that result in differences between regional faunas acting at broad extents). Whereas climatic factors have been widely studied, the effects of regional differences are less often quantified. This work aims to characterize global trends in the species richness of mammal assemblages with respect to both current and historical influences.Location  All terrestrial biogeographical realms except Antarctica.Methods  Species richness in checklists from 224 sites distributed worldwide were investigated by partitioning the variation between a general set of habitat/climate factors, biogeographical regions, and their overlaps. Additional analyses studied the specific overlaps of region, water and energy. Data were also divided according to area to determine if the strength of these effects varies according to the size of sites.Results  Environmental effects explained 38% of richness variation across all sites, whereas environmentally independent regional effects explained 11% and the overlap between region and environment explained 13%. Results were similar when only larger sites (between 1000 km2 and 10,000 km2) were considered. However, the importance of the overlap between region and all environmental variables was greater in smaller sites (between 100 km2 and 1000 km2). In contrast, the specific importance of water and energy variables and their overlap with region was greater in larger sites. The strength of the independent effect of region remained almost invariant regardless of the size of the sites studied.Main conclusions  The relationship between species richness and climate varies with scale and among regions. Although environmental variables are the strongest correlates of richness, the unique history and physiographic characteristics of a region produce differences between the richness of mammal assemblages and their response to environmental gradients. The importance of environmental variables varies with scale: climatic gradients are more important at coarse grain (larger sites), possibly as a result of their effects on species ranges, whereas habitat type is more important at the smaller sites, where the importance of ecological interactions increases. Therefore, regional differences and the scale at which richness is measured should be taken into account when evaluating species richness–energy hypotheses.

Competition has long been proposed as an important force in structuring mammalian communities. Although early work recognized that competition has a phylogenetic dimension, only with recent increases in the availability of phylogenies have true phylogenetic investigations of mammalian community structure become possible. We test whether the phylogenetic structure of 142 assemblages from three mammalian clades (New World monkeys, North American ground squirrels and Australasian possums) shows the imprint of competition. The full set of assemblages display a highly significant tendency for members to be more distantly related than expected by chance (phylogenetic overdispersion). The overdispersion is also significant within two of the clades (monkeys and squirrels) separately. This is the first demonstration of widespread overdispersion in mammal assemblages and implies an important role for either competition between close relatives where traits are conserved, habitat filtering where distant relatives share convergent traits, or both.