I. Biodiversity in a human-dominated world
II. The Tiger: A species on the brink
Part I. Biodiversity in a human-dominated world
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In her first talk, Dr. Hadly explains how a growing human population has led to a striking loss of biodiversity worldwide. Today, 51% of land area has been converted to human use and the small areas of land that are protected are becoming increasingly isolated. These shrinking “islands” of protected land support fewer species. Isolated small populations show increased inbreeding and reduced genetic diversity making them more vulnerable to collapse. Climate change is exacerbating this loss of biodiversity by forcing animals to migrate and introducing them to novel species and diseases. Hadly illustrates her talk with stories of both populations under threat as well as those that have successfully rebounded.
Tigers are typically portrayed as powerful predators that dominate their environments, however, their numbers have been dramatically declining for years. Historically, tigers ranged throughout most of Southeast Asia. As the number of humans has grown, tigers have been forced into small, distantly separated populations, or subspecies, reducing genetic diversity within each group. In her second talk, Hadly explains models developed in her lab to study the impact of interbreeding between these separate populations. They showed that increasing gene flow between subspecies, via artificial insemination or assisted migration, would greatly increase genetic diversity and improve the likelihood that tigers will survive.
Elizabeth Hadly is the Paul S. and Billie Achilles Chair of Environmental Science and a professor of biology at Stanford University. She is a Senior Fellow in the Stanford Woods Institute for the Environment, and, in September 2016, Hadly will become the Faculty Director for the Stanford Jasper Ridge Biological Preserve.
Hadly’s lab studies the ecology and evolution of vertebrates. In particular, they are interested in how vertebrates, from amphibians to mammals, have responded to environmental changes over the past 10,000 years. Projects span the globe from North and South America to Asia.
In addition to her research commitments, Hadly is senior associate Vice Provost for undergraduate education. She is also a scientific advisor to California Governor Jerry Brown and an advocate for effective scientific communication. Hadly and University of California, Berkeley paleoecologist Anthony Barnosky together wrote a consensus statement on climate change that Governor Brown has used to inform and influence policy makers nationally and internationally.
Hadly received her BA in Anthropology at the University of Colorado, Boulder, her MS in Quaternary Science at Northern Arizona University, Flagstaff and her PhD in Integrative Biology at the University of California, Berkeley.
Learn more about Liz Hadly here.
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Barnosky AD, Ehrlich PR, and Hadly EA. 2016. Avoiding collapse: Grand challenges for science and society to solve by 2050. Elementa DOI 10.12952/journal.elementa.000094
Barnosky AD, Lindsey EL, Villaviciencio NA, Bostelmann E, Hadly EA, Wanket J, and Marshall CR. 2015. Variable impact of late-Quaternary megafaunal extinction in causing ecological state shifts in North and South America. PNAS 113(4): 856–861
Barnosky AD, Brown JH, Daily GC, Dirzo R, Ehrlich AH, Ehrlich PR, Eronen JT, Fortelius M, Hadly EA, Leopold EB, Mooney HA, Myers JP, Naylor RL, Palumbi S, Stenseth NC, and Wake MH. 2014. Introducing the Scientific Consensus on Maintaining Humanity’s Life Support Systems in the 21st Century: Information for Policy Makers. The Anthropocene Review 1(1):78-109
Bay RA, Ramakrishnan U, and Hadly EA. 2014. A Call for Tiger Management Using “Reserves” of Genetic Diversity. J. Heredity 105(3): 295-302
Ramakrishnan U, Hadly EA and Mountain J. 2005. Detecting past population bottlenecks using temporal genetic data. Mol. Ecol. 14: 2915-2922.