Novacek, Michael J., American Museum of Natural History, EF 0629811 Murphy, William J., Texas A & M Research Foundation, EF 0629849 O'Leary, Maureen A., SUNY Stony Brook, EF 0629836 Luo, Zhe-Xi, Carnegie Institute, EF 0629959 Springer, Mark, Univ. California, Riverside, EF 0629860
Abstract Only a few of the myriad biological groups now thriving on this planet have fossil records that chronicle their evolutionary past. One of these few is Mammalia, known from about 5,000 extant species distributed among 1135 living genera, including our own human lineage, and more than 4,000 extinct genera, a four-to-one ratio of fossil genera to living genera that can hardly be matched elsewhere in the biota. Mammals display a spectacular range in size, form, and adaptations. They are closely linked to human health, welfare, and experience. No tree of all life could be regarded as complete without a comprehensive phylogeny of Mammalia. This conviction has inspired a surge of work in paleontology, comparative anatomy, and molecular biology. Despite these significant gains, many aspects of mammalian phylogeny are unresolved or highly controversial, even at some of the major branching points on the mammalian tree. PIs propose to examine species exemplars for 135 extant families, the majority of some 350 extinct families, and to extend this sample to a generic-level data set of 500 extant and nearly 500 extinct genera for combined analysis of genes and morphology. Their molecular team will continue to sample taxa toward a goal of covering 95% of all living genera outside the murids (rats, mice, and kin) and sciurids (squirrels). For character evidence, PIs plan to sample 30Kb in gene sequences from 34 genes for at least one exemplar of all living families. For the larger generic-level phases of the project, they will sample at least 6Kb of sequence. Morphologists will collect a projected 2,000 characters. Completion of a broad scale phylogeny for mammals will provide a model system in evolutionary and comparative biology with numerous applications in conservation and wildlife management, human health, biomedicine, and other areas. In addition, PIs intend to compile an integrated and image rich database for mammalian characters and convert it into a powerful toolkit for conservation management, education, and outreach through training programs and web resources.
The goal for this Assembling the Tree of Life project is to produce a phylogeny for mammals that for the first time represents the integration and analysis of gene sequence and morphological data across all major clades. Mammals are one of a few of the myriad biological groups now thriving on this planet that have fossil records that chronicle their important evolutionary past. Mammals occupy key roles as species in both marine and terrestrial ecosystems. They display a spectacular range in size, form, and adaptations. They are closely linked to human health, welfare, and experience. No tree of all life could be regarded as broadly complete without a comprehensive phylogeny of Mammalia. Our project developed a complete phylogeny of all 135 living mammalian families, as well as a few extinct families, using a large nuclear gene sequence data set. We then extended our project to sample >90% of all living genera and >75% of living species in a complete phylogeny using new and published DNA sequence data. Our findings provide insight into the roles that past climate change and events in earth history played in the diversification of mammals. We also developed novel methods to retrieve large amounts of targeted DNA sequence from small amounts of museum specimens. These methods will allow for a more thorough utlilization of specimens in natural history collections, providing for analysis of recently extinct species as well as those that are rare or difficult to study in the wild. Completion of this broad scale phylogeny for mammals serves as a model system in evolutionary and comparative biology with numerous applications in conservation and wildlife management, human health, biomedicine and other areas. We trained several postdoctoral researchers, graduate students and undergraduate students, exposing them to different aspects of mammal biology, conservation, evolution and the tree of life project. Our collaboration includes members of natural history museums and a zoo, who will translate our research outcomes on mammalian evolution into displays that will be appreciated by tens of millions of public viewers of diverse economic and societal backgrounds.
