Protected areas (PAs) are a cornerstone of conservation efforts and now cover nearly 13% of the world's land surface, with the world's governments committed to expand this to 17%. However, as biodiversity continues to decline, the effectiveness of PAs in reducing the extinction risk of species remains largely untested. We analyzed PA coverage and trends in species' extinction risk at globally significant sites for conserving birds (10,993 Important Bird Areas, IBAs) and highly threatened vertebrates and conifers (588 Alliance for Zero Extinction sites, AZEs) (referred to collectively hereafter as ‘important sites’). Species occurring in important sites with greater PA coverage experienced smaller increases in extinction risk over recent decades: the increase was half as large for bird species with>50% of the IBAs at which they occur completely covered by PAs, and a third lower for birds, mammals and amphibians restricted to protected AZEs (compared with unprotected or partially protected sites). Globally, half of the important sites for biodiversity conservation remain unprotected (49% of IBAs, 51% of AZEs). While PA coverage of important sites has increased over time, the proportion of PA area covering important sites, as opposed to less important land, has declined (by 0.45–1.14% annually since 1950 for IBAs and 0.79–1.49% annually for AZEs). Thus, while appropriately located PAs may slow the rate at which species are driven towards extinction, recent PA network expansion has under-represented important sites. We conclude that better targeted expansion of PA networks would help to improve biodiversity trends.
Studies of a diverse array of animals have found that young individuals often have robust bones for their body size (i.e. augmented crosssectional dimensions), limiting fracture risk despite general musculoskeletal immaturity. However, previous research has focused primarily on precocial taxa (e.g. rodents, lagomorphs, bovids, goats and emu). In this study, we examined the ontogenetic scaling of humeral and femoral cross-sectional robusticity in a mixedlongitudinal sample of two slow-growing, behaviourally altricial capuchin monkeys. Results showed that, when regressed against biomechanically appropriate size variables (i.e. the product of body mass and bone length), humeral and femoral bending strengths generally scale with negative allometry, matching the scaling patterns observed in previous studies of more precocial mammals. Additionally, bone strength relative to predicted loads (e.g. 'safety factors') peaks at birth and rapidly decreases during postnatal growth, falling to less than 5 per cent of peak values by weaning age. We suggest that increased safety factors during early ontogeny may be an adaptation to mitigate injury from falling during initial locomotor efforts. Overall, the results presented here suggest that ontogenetic declines in relative long bone strength may represent a common pattern among mammals that is perhaps preadaptive for different purposes among different lineages.
The “scaly-tailed squirrels” of the rodent family Anomaluridae have a long evolutionary history in Africa, and are now represented by two gliding genera (Anomalurus and Idiurus) and a rare and obscure genus (Zenkerella) that has never been observed alive by mammalogists. Zenkerella shows no anatomical adaptations for gliding, but has traditionally been grouped with the glider Idiurus on the basis of craniodental similarities, implying that either the Zenkerella lineage lost its gliding adaptations, or that Anomalurus and Idiurus evolved theirs independently. Here we present the first nuclear and mitochondrial DNA sequences of Zenkerella, based on recently recovered whole-body specimens from Bioko Island (Equatorial Guinea), which show unambiguously that Zenkerella is the sister taxon of Anomalurus and Idiurus. These data indicate that gliding likely evolved only once within Anomaluridae, and that there were no subsequent evolutionary reversals. We combine this new molecular evidence with morphological data from living and extinct anomaluromorph rodents and estimate that the lineage leading to Zenkerella has been evolving independently in Africa since the early Eocene, approximately 49 million years ago. Recently discovered fossils further attest to the antiquity of the lineage leading to Zenkerella, which can now be recognized as a classic example of a “living fossil,” about which we know remarkably little. The osteological markers of gliding are estimated to have evolved along the stem lineage of the Anomalurus–Idiurus clade by the early Oligocene, potentially indicating that this adaptation evolved in response to climatic perturbations at the Eocene–Oligocene boundary (∼34 million years ago).
The ability to increase energy storage when food is abundant for later use during late gestation and early lactation is often considered the primary benefit of the capital breeding strategy (clustering conceptions during high food periods, HFP) that promotes reproductive success among females living in unpredictable environments. Capital breeding, however, may also enable preconceptive females to increase hormone production for ovulation, which has been linked to energetic condition in capital breeders, and/or allow females entering the subsequent HFP to increase their energetic condition in order to continue nursing unweaned infants. Here, we investigate whether capital breeding provides these additional benefits in 16 female Sanje mangabeys (Cercocebus sanjei) and determine the dietary strategies used to increase energetic condition (measured by urinary C-peptide: UCP) during the HFP. Fecal estradiol (fE2 ) and UCP were negatively correlated with number of cycles before conception (r = -0.591, r = -0.646, P < 0.01) and were highest in conceptive cycles. Both peri-conceptive (preconception and early gestation) and non-peri-conceptive (lactation) females increased energetic condition over the HFP (r = 0.612, r = 0.583, P < 0.001) by increasing dietary fat (r = 0.619, r = 0.703, P < 0.001) and, for non-peri-conceptive females, protein (r = 0.437, P < 0.001). Feeding intake rate (FIR) and time spent foraging and feeding did not change over the HFP; however, non-peri-conceptive females exhibited a faster FIR compared to peri-conceptive females (t = -2.324, P < 0.05), consuming almost twice as much food per unit time. The results of this study confirm that Sanje mangabeys benefit in multiple phases of the reproductive cycle by using capital breeding, which may explain how this strategy promotes female reproductive success.
Over the past decades, primate populations have been declining. Four years ago, >60% of species were listed as threatened. As the rate of loss accelerates and new IUCN assessments are being published, we used IUCN Red List assessments and peer-reviewed literature published within the last 5 yr to evaluate the status of primates globally, by region and by taxonomic group. We also examined the main factors affecting a species’ conservation status to determine if we could predict the status of understudied species. We found that 65% of species are in the top three IUCN Red List categories (Vulnerable, Endangered, Critically Endangered). Globally, the main threats to primates are Biological Resource Use, including Hunting & Logging, and Agriculture. The impact of these threats varied by region and taxon. Our model showed that Malagasy and Asian primates, and those affected by Agriculture, Human Disturbance, and Climate Change were more likely to be considered at risk of extinction. The model’s predictive probability, however, was low. Our literature analysis showed that some threats, especially climate change and disease, affected more species than indicated by the IUCN Red List. As we move into the next decade, we must continue tackling hunting and agricultural expansion but also be vigilant about emerging threats. We must also aim to regularly test the effectiveness of mitigation strategies, evaluating their long-term adoption and their impact on primates; as well as to increase communication between researchers and applied conservationists to ensure IUCN assessments include current and emerging threats.
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