Saving the world’s terrestrial megafauna

From the late Pleistocene to the Holocene, and now the so called Anthropocene, humans have been driving an ongoing series of species declines and extinctions (Dirzo et al. 2014). Large-bodied mammals are typically at a higher risk of extinction than smaller ones (Cardillo et al. 2005). However, in some circumstances terrestrial megafauna populations have been able to recover some of their lost numbers due to strong conservation and political commitment, and human cultural changes (Chapron et al. 2014). Indeed many would be in considerably worse predicaments in the absence of conservation action (Hoffmann et al. 2015). Nevertheless, most mammalian megafauna face dramatic range contractions and population declines. In fact, 59% of the world’s largest carnivores (≥ 15 kg, n = 27) and 60% of the world’s largest herbivores (≥ 100 kg, n = 74) are classified as threatened with extinction on the International Union for the Conservation of Nature (IUCN) Red List (supplemental table S1 and S2). This situation is particularly dire in sub-Saharan Africa and Southeast Asia, home to the greatest diversity of extant megafauna (figure 1). Species at risk of extinction include some of the world’s most iconic animals—such as gorillas, rhinos, and big cats (figure 2 top row)—and, unfortunately, they are vanishing just as science is discovering their essential ecological roles (Estes et al. 2011). Here, our objectives are to raise awareness of how these megafauna are imperiled (species in supplemental table S1 and S2) and to stimulate broad interest in developing specific recommendations and concerted action to conserve them

The status of the world's land and marine mammals: diversity, threat, and knowledge

Knowledge of mammalian diversity is still surprisingly disparate, both regionally and taxonomically. Here, we present a comprehensive assessment of the conservation status and distribution of the world's mammals. Data, compiled by 1700+ experts, cover all 5487 species, including marine mammals. Global macroecological patterns are very different for land and marine species but suggest common mechanisms driving diversity and endemism across systems. Compared with land species, threat levels are higher among marine mammals, driven by different processes (accidental mortality and pollution, rather than habitat loss), and are spatially distinct (peaking in northern oceans, rather than in Southeast Asia). Marine mammals are also disproportionately poorly known. These data are made freely available to support further scientific developments and conservation action

New News From the Adult Changes in Thought Study: A Long-Standing Living Laboratory of Aging Funded for Five More Years

Background/Aims: Delivery system-based research in enumerated populations provides a unique opportunity to study complex chronic diseases as they develop. Studies of disorders that affect people late in life can be particularly valuable. The Adult Changes in Thought (ACT) study was recently awarded five more years of funding. This makes ACT one of the longest continually funded studies and establishes it as a preeminent living laboratory for aging research. Methods: Originally a joint project between Group Health and the University of Washington, the ACT study recruited a cohort of randomly selected Group Health enrollees over age 65 without dementia from 1994 to 1996. Initially 2,581 persons were recruited, but in response to cohort shrinkage over time, we developed expansion and ongoing replacement strategies to maintain a currently active cohort of approximately 2,000 living persons who are followed every 2 years. The original outcomes of interest in ACT were Alzheimer’s disease and related dementias based on standardized diagnostic methods supplemented by neuropathologic outcomes. This funding cycle we’ve added a new outcome “resilience” to specifically study persons who defy expectations by avoiding cognitive decline and frailty well into late life. Results: ACT has enrolled over 5,000 subjects to date and includes over 1,000 cases of incident dementia (over 70% Alzheimer’s disease) and over 600 autopsy cases, of which about half have extensive frozen tissues from a rapid autopsy protocol. The laboratory now includes a biobank with a vast array of genomic information along with a population-based neuropathology biobank that is unique worldwide. The new funding cycle will include state-of-the-art measures of physical activity (e.g. accelerometers, inclinometers) to determine how physical activity and sedentary time affect outcomes, especially resilience, and also include unique neuropathologic markers (synaptosomes and histelide) to better understand brain aging. ACT has always supported other investigations, and we are well equipped to support HCSRN scientists who wish to use our living learning laboratory of aging. Conclusion: The long-running ACT study in the new funding cycle will focus on the science of aging and multimorbidity, understanding resiliency and robust aging, and sharing data from our extensive data repository for other studies of interest