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Published: March 18, 2013

What's in a name: taxonomy Serving Conservation

Bruce Patterson, MacArthur Curator of Mammals, Integrative Research Center

 

Human persecution of lions has resulted in geographic range collapse and declining populations where they remain.

 

To understand the consequences of range and population collapse, we surveyed the genetics of more than 500 lions from throughout their remaining range, both in Africa and in Asia.   Most of the sequencing and all the microsatellite analyses were done in Dr. Dubach’s laboratory at Loyola University.
 

 

There are two major branches of lions: (1) East and South Africa, and (2) Asia and West and Central Africa.
 

Gene substitution networks also show that Asian lions are much closer to those in West and Central Africa than this group is to other African lions.

 

This map shows Lion Conservation Units (in blue) and haplotypes (coded letters) of the cytochrome-b gene for our 120 samples.  The dotted line separates the two principal genetic lineages of living lions, with Asian lions belonging to the West and Central African clade.

 

This Structure diagram classifies individual lions by their microsatellites and shows relatively homorgenous populations (like Etosha and Kunene) and highly heterogeneous ones (like the Caprivi Strip and Kwando in Botswana).

 

In late 2012, the US Fish & Wildlife Service reviewed a petition for uplisting of lions to Endangered Species status.  This move would effectively eliminate sport hunting of lions, as no US sportsmen would be permitted to import trophies.  Vast areas of the African savanna are managed as hunting concessions, remaining in native vegetation because revenue from trophy fees offsets the costs of maintaining them.  Although uplisting lions would surely reduce mortality from hunting, it could bankrupt many concessions and trigger wholesale land conversions to agriculture.

 

Authorities currently organize international law around Panthera leo leo (African lions) and Panthera leo persica (Asian lions).  However, our analyses show that this does not represent an accurate picture of genetic diversity in living lions. Much larger differences exist among African lions than those between African and Asian lions.  So at least three subspecies are needed to encompass the diversity of lions today: (1) persica, for the Asian lions, (2) leo for the extinct Barbary lion and closely related forms from West and Central Africa, and (3) melanochaita for a large, heterogeneous assemblages of lions in Eastern and Southern Africa.  The last-named group is far more diverse than the prior two, but lions are highly variable and delimiting regional variants within this last form is difficult.  Coordinated studies of genetic, cranial and pelage variation will be needed to arrive at a truly satisfying taxonomy. However, it is important to note that even three names would allow resource managers to better conserve lions.  Only 300 individuals of persica and 500 of leo remain, so these populations clearly warrant the highest levels of federal and international protection.  However, more than 32,000 lions live within the range of what is here treated as melanochaita; accordingly, limited offtake to sport hunting may be manageable for this form if (a) it is very carefully regulated and (b) it raises the revenue needed to prevent further fragmentation and loss of the savanna habitats on which both lions and their prey depend. To learn more about this work, see our recent paper: Dubach, J.M., M.B. Briggs, P.A. White, B.A. Ament & B.D. Patterson*. 2013. Genetic perspectives on “Lion Conservation Units” in Eastern and Southern Africa. Conservation Genetics DOI: 10.1007/s10592-013-0453-3.

To see other research from our laboratory, visit these pages:

http://sites.google.com/a/fieldmuseum.org/bruce-pattersons-lab/


Bruce Patterson

I study several topics in evolutionary biology, focusing on the diversification, distribution and conservation of mammals. The breadth of my research is testimony to the facts that no interesting biological questions are ever fully answered and progress towards answering them invariably opens up a variety of others.  Curiosity, opportunity, and a bit of wanderlust have diversified my program and caused it to span two continents.

 

Density of terrestrial vertebrate species (savingspecies.org). Wonder why I study tropical animals?!

For most of my career, I have used museum specimens to study the systematics and biogeography of Neotropical mammals.  Collaborating with scientists and students in Ecuador, Peru, Bolivia, Brazil, and Chile, I have worked throughout the Andes, Amazonia, as well as Atlantic, Valdivian, and Magellanic Forests. While documenting some of the world's richest and most highly endemic faunas, we regularly discover and describe new taxa of marsupials, rodents, and bats and use them in regional and continental reconstructions of phylogeny and biogeography. The program offers abundant training opportunities for American and Latin American students, both in the lab and in the field.  Beginning in 2011, I started a parallel project on the The Bats of Kenya with colleagues Paul Webala and Carl Dick.  This project is designed to document the distribution and status of more than 100 species of bats that occur in Kenya and to shed light on their ecological roles and current status.

Collecting parasites in the course of these systematic studies led to my interest in host-parasite coevolution.  Ectoparasites recovered from mammals and birds are used to reconstruct the radiation of parasite groups and to assess their distributions across hosts and geography.  These studies identify factors that govern the distribution, abundance, and host specificity of parasites.  Together with Carl Dick (until 2009 a post-doc here at the Museum, now at Western Kentucky University) and Katharina Dittmar (SUNY Buffalo), we have developed a broad range of studies on the ecology, coevolution, and phylogeny of these interesting flies.  Interest in the unstudied ectoparasite communities of African bats helped fuel our collaborations with Kenyan Paul Webala to survey the diverse bat communities of Kenya.        

 

A Hipposideros bat with an ectoparasitic Penicillidia bat fly

A second, derivative program focuses on host-parasite coevolution.  Ectoparasites recovered from mammal and bird specimens are used to reconstruct the evolutionary radiations of parasite groups and assess their current distributions across hosts and geography, factors governing their distribution, abundance, and host specificity.  Work on bat flies has been developed with Carl Dick (until 2009 a post-doc here at the Museum, but now at Western Kentucky University) and Katharina Dittmar (SUNY Buffalo) on their ecology and phylogeny. With NSF funding, we recently curated the world's largest collection of flies, which now guides our understanding of host associations and fuels the taxon-sampling in our phylogenetic work (also supported by NSF). Undergrad and grad students are involved in this work in Chicago, Buffalo, and Bowling Green. Interest in the mostly unexplored ectoparasite communities of African bats helped fuel my collaboration with Kenya Wildlife Service ecologist Paul Webala on surveying the diverse bat communities of Kenya (see above). 

Photo by B. A. Harney in Tsavo, Kenya (July 2007)
 

A research program that I am now concluding focused on the Tsavo lions, infamous as man-eaters a century ago but more remarkable because many of them lack manes. In a series of papers, I have explored the morphology, genetics, behavior, and ecology of lions in SE Kenya with Samuel Kasiki (Kenya Wildlife Service) and Alex Mwazo (Kenyatta University), Roland Kays (NY State Museum), Jean Dubach (Loyola University), Justin Yeakel (UC Santa Cruz), and others.  Our aim has been to understand this distinctive and environmentally-plastic trait (manelessness) at genetic, hormonal, histological, anatomical, and behavioral levels. Concurrently, we gathered information to mitigate the impacts of lion depredations on livestock to ensure their continued survival and the preservation of their habitats. Until 2009, this project had the help of volunteers from the Earthwatch Institute.

As detailed in Students, interactions with undergraduate and graduate students enrich, extend, and complement these studies. All four research arenas offer opportunities for student research projects and post-graduate collaborations alike.