The planetary boundaries framework defines a safe operating space for humanity based on the intrinsic biophysical processes that regulate the stability of the Earth system. Here, we revise and update the planetary boundary framework, with a focus on the underpinning biophysical science, based on targeted input from expert research communities and on more general scientific advances over the past 5 years. Several of the boundaries now have a two-tier approach, reflecting the importance of cross-scale interactions and the regional-level heterogeneity of the processes that underpin the boundaries. Two core boundaries—climate change and biosphere integrity—have been identified, each of which has the potential on its own to drive the Earth system into a new state should they be substantially and persistently transgressed.

/pdf/planetary-boundaries-guiding-human-development-on-a-changing-5gmf909etg.pdf

Planetary boundaries: Guiding human development on a changing planet

Food in the Anthropocene: the EAT–Lancet Commission on healthy diets from sustainable food systems

Many studies in recent years have investigated the effects of climate change on the future of biodiversity. In this review, we first examine the different possible effects of climate change that can operate at individual, population, species, community, ecosystem and biome scales, notably showing that species can respond to climate change challenges by shifting their climatic niche along three non-exclusive axes: time (e.g. phenology), space (e.g. range) and self (e.g. physiology). Then, we present the principal specificities and caveats of the most common approaches used to estimate future biodiversity at global and sub-continental scales and we synthesise their results. Finally, we highlight several challenges for future research both in theoretical and applied realms. Overall, our review shows that current estimates are very variable, depending on the method, taxonomic group, biodiversity loss metrics, spatial scales and time periods considered. Yet, the majority of models indicate alarming consequences for biodiversity, with the worst-case scenarios leading to extinction rates that would qualify as the sixth mass extinction in the history of the earth.

/pdf/impacts-of-climate-change-on-the-future-of-biodiversity-3rngjb4k3z.pdf

Impacts of climate change on the future of biodiversity.

We live amid a global wave of anthropogenically driven biodiversity loss: species and population extirpations and, critically, declines in local species abundance. Particularly, human impacts on animal biodiversity are an under-recognized form of global environmental change. Among terrestrial vertebrates, 322 species have become extinct since 1500, and populations of the remaining species show 25% average decline in abundance. Invertebrate patterns are equally dire: 67% of monitored populations show 45% mean abundance decline. Such animal declines will cascade onto ecosystem functioning and human well-being. Much remains unknown about this “Anthropocene defaunation”; these knowledge gaps hinder our capacity to predict and limit defaunation impacts. Clearly, however, defaunation is both a pervasive component of the planet’s sixth mass extinction and also a major driver of global ecological change.

/pdf/defaunation-in-the-anthropocene-46k054u5cx.pdf

Defaunation in the Anthropocene

The oft-repeated claim that Earth’s biota is entering a sixth “mass extinction” depends on clearly demonstrating that current extinction rates are far above the “background” rates prevailing between the five previous mass extinctions. Earlier estimates of extinction rates have been criticized for using assumptions that might overestimate the severity of the extinction crisis. We assess, using extremely conservative assumptions, whether human activities are causing a mass extinction. First, we use a recent estimate of a background rate of 2 mammal extinctions per 10,000 species per 100 years (that is, 2 E/MSY), which is twice as high as widely used previous estimates. We then compare this rate with the current rate of mammal and vertebrate extinctions. The latter is conservatively low because listing a species as extinct requires meeting stringent criteria. Even under our assumptions, which would tend to minimize evidence of an incipient mass extinction, the average rate of vertebrate species loss over the last century is up to 100 times higher than the background rate. Under the 2 E/MSY background rate, the number of species that have gone extinct in the last century would have taken, depending on the vertebrate taxon, between 800 and 10,000 years to disappear. These estimates reveal an exceptionally rapid loss of biodiversity over the last few centuries, indicating that a sixth mass extinction is already under way. Averting a dramatic decay of biodiversity and the subsequent loss of ecosystem services is still possible through intensified conservation efforts, but that window of opportunity is rapidly closing.

http://biospherology.com/PDF/mass_extinction.pdf

Accelerated modern human-induced species losses: Entering the sixth mass extinction

Palaeontologists characterize mass extinctions as times when the Earth loses more than three-quarters of its species in a geologically short interval, as has happened only five times in the past 540 million years or so. Biologists now suggest that a sixth mass extinction may be under way, given the known species losses over the past few centuries and millennia. Here we review how differences between fossil and modern data and the addition of recently available palaeontological information influence our understanding of the current extinction crisis. Our results confirm that current extinction rates are higher than would be expected from the fossil record, highlighting the need for effective conservation measures.

/pdf/has-the-earth-s-sixth-mass-extinction-already-arrived-dzhs0k1eir.pdf

Has the Earth’s sixth mass extinction already arrived?

Here we describe dental remains from a Neanderthal fossil assemblage from Moula-Guercy, France. Our report demonstrates that the Moula-Guercy hominid remains contribute important morphological, developmental, and behavioral data to understanding Neanderthal evolutionary history. We include gross comparative morphological descriptions and enamel surface microstructure and microwear data. These teeth reveal numerous characteristics that are diagnostic of Neanderthals and provide no evidence for the presence of any other hominid taxa. Enamel growth increment data from the Moula-Guercy specimens yield evidence of a Neanderthal pattern of development, although at the lower end of the range of variation. The presence of a significant number of linear enamel hypoplasias indicates that these individuals were stressed during childhood. Molar microwear data suggest that these Neanderthals did not differ significantly from modern humans in terms of the fracture properties of the food they were consuming. The incisor microwear and macro striations provide evidence that these individuals may have been using their anterior teeth as tools, similar to the practices of several modern human populations such as the Inuit, Ipiutak, and Australian Aboriginals, and reminiscent of evidence from other Neanderthals from Krapina, Croatia, as well as the 600,000 year old hominids from Sima de los Huesos, Spain. Am J Phys Anthropol 151:477-491, 2013.© 2013 Wiley Periodicals, Inc.

Neanderthal teeth from Moula-Guercy, Ardèche, France.

The hand and foot remains from Moula- Guercy cave (Ardeche, France) comprise 24 specimens of Eemian age (ca. 120 ka). The specimens include primar- ily complete elements, which are rare among the Moula- Guercy postcrania. The hand remains have several characteristic Neanderthal traits including a laterally facing (parasagittally oriented) second metacarpal- capitate articulation, a short styloid process, a wide proximal articular surface on the third metacarpal, and absolutely expanded apical tuberosities on the distal hand phalanges relative to modern humans. The foot remains include several incomplete elements along with an antimeric pair of naviculars, a medial cuneiform and cuboid, and a single complete element from each of the distal segments (one each: metatarsal, proximal foot phalanx, intermediate foot phalanx, distal foot phalanx). Consistent among the specimens are relatively wide dia- physes for length in the metatarsals and phalanges and large and prominent muscle attachments, both consist- ent with previously published Neanderthal morphology. The hand and foot collection from Moula-Guercy is an important dataset for future studies of Neanderthal functional morphology, dexterity, and behavior as it rep- resents a previously undersampled time period for Euro- pean Neanderthals. Am J Phys Anthropol 152:516-529,

Neanderthal hand and foot remains from Moula-Guercy, Ardèche, France.

Excavations carried out during the 1990s at Moula-Guercy cave Ardeche, France, yielded 108 homi- nid specimens dating to 100-120 Ka. In this paper, we describe and compare the 39 axial and appendicular specimens not including hand and foot bones. Among these remains are a large adult femur, several clavicles, a likely antimeric pair of radial heads, and a nearly com- plete superior pubic ramus. Analyses of this material indicate a clear affinity with Neanderthals by the pres- ence of large and robust muscle attachments, thick long bone cortices, a long pubic ramus, and a superoinferiorly flattened clavicle shaft. The recovered remains reveal the presence of a mature male, a smaller mature individual, possibly a reproductive age female, an immature individ- ual of age 10-12, and a second immature individual of age 4. Future analyses on the Moula-Guercy remains will illuminate ties to other known Neanderthal populations and contribute to the ongoing debate over the relative rate of Neanderthal metric growth. Am J Phys Anthropol

Ben Mersey

Papers

Has the Earth’s sixth mass extinction already arrived?

Neanderthal teeth from Moula-Guercy, Ardèche, France.

Neanderthal hand and foot remains from Moula-Guercy, Ardèche, France.

Neanderthal axial and appendicular remains from Moula-Guercy, Ardèche, France