Research Projects

2001 Expedition to Bwindi Impenetrable Forest in Uganda supported by

My colleague Dr. Dennis Cullinane at Boston University and I lead an expedition to the Bwindi Impenetrable Forest in Uganda in the summer of 2001, with funding from the National Geographic Society. The goal of the project was to study a rare and enigmatic small mammal, the hero shrew.

Background:

The spine of Scutisorex somereni (the hero shrew) has been modified beyond anything that has been identified in the history of vertebrates. This anatomy is highly unusual because the spine is typically the most morphologically conservative structure in the vertebrate skeleton. The complexity of the vertebral column was not recognized until 1917, when Allen published a description of the skeletal anatomy. Allen was led to this intriguing discovery after reading an expedition account by Herbert Lang that described a ceremony performed by the Mangbetu people of Rwanda. According to Lang's account, a tribesman places one foot carefully on the back of a captive hero shrew and, concentrating all his weight on that one foot, stands on the shrew. The hero shrew survives the ordeal unharmed because of the anatomical modifications of its vertebrae. The hero shrew (or armored shrew) capable of supporting up to 1000 times its body mass on its back, the equivalent of 10 elephants on the back of an adult human. Despite the novelty of the hero shrew spine, no associated function has been identified because the ecology and behavior of this species is poorly documented.

Our objectives are threefold:

1) To observe hero shrews in the wild and identify a set of behaviors that can be correlated with their elaborate spinal anatomy.

2) To describe the basic life history and ecology of this little known species before its restricted habitat is further fragmented and degraded.

3) To further clarify the functional/biomechanical properties of the elaborate vertebrae begun by Cullinane and his co-workers in 1998 in an effort to ascertain if there are any medical applications that might be used to fight osteoporosis.

The Ghana Coastal Wetlands Management Project

Ghana's 550 km of coastline includes over one hundred estuaries and lagoons. These coastal wetlands are on the boundary of two major migration corridors for waterbirds: the East Atlantic Flyway and the Mediterranean Flyway. Studies by the Save the Sea Shore Birds - Project and the Ghana Wildlife Society dating back to the early 1980s, have shown that significant numbers of waterbirds use Ghana coastal wetlands as staging areas and wintering grounds. At least 15 species of waterbirds occur here in internationally important populations (Ntiamoa-Baidu, 1991).

Five coastal lagoons and their watersheds along the Ghana coast have been proposed as Ramsar Sites (internationally important wetlands) under the Convention on Wetlands of International Importance (Ramsar Convention). In 1992, the government of Ghana received support from the Global Environment Facility (GEF), for the protection of these sites (Muni-Pomadze, Densu delta, Sakumo, Songor, and Keta) under the Coastal Wetlands Management Project (CWMP), which is implemented by the Ghana Wildlife Department.

The CWMP seeks to preserve the ecological integrity of these five coastal wetlands, and to enhance the socio-economic benefits that these wetlands provide to the local communities (Ntiamoa-Baidu and Gordon, 1991; Piersma and Ntiamoa-Baidu, 1995). To fulfil the CWMP's goals, baseline information on the ecological health and integrity of these wetland ecosystems is required before sound management decisions can be made. Toward that end, the CWMP has implemented a series of baseline ecological studies aimed at characterizing the current status of these important wetlands. These ecological studies will form the basis for management and additional long-term monitoring of these sites. The Muni-Pomadze Ramsar Site has the greatest habitat diversity and least encroachment by human populations of the five Ramsar sites, making it an ideal nature reserve. With excellent ocean views, coconut fringed sandy beaches, and diverse bird and butterfly communities, educational and ecotourism markets are promising.

For details on this project please refer to the Special Edition of the journal Biodiversity and Conservation April 2000. I served as project leader of the terrestrial survey.

I worked in Madagascar on three different projects over the years. The first project was to survey mammals for a proposed new Ranomafana National Park. Ranomafana National Park is located in Fianarantsoa Province of eastern Madagascar. It officially became a national park on May 31, 1991.

Ranomafana National Park consists of a 41,500 hectare core zone surrounded by a multiuse boundary zone that contains about 100 small villages. The core zone is located in an extremely mountanus region; the steep slopes have no doubt protected the forests from logging. In 1986, a new lemur species, Hapalemur aureus, was discovered in the forest, and at about the same time Hapalemur simus was rediscovered in the same region. Ranomafana National Park is home to 13 lemur species. The forests include lowland rainforest to montane cloud forests and they house hundreds of rare and endangered species of plants and animals.

I also worked surveying primates on a project in southern Madagascar. You can find out more about Ranomafana National Park at ICTE.

My students and I are currently studying the visual system of bats. Much attention has been focused on the role of echolocation in bats, but very little research has been conducted on the visual acquity of bats. We are comparing the retinal anatomy of a wide range of bats in order to understand the role the eyes play in bat sensory ecology.

I am also interested in the neuromuscular system of bats and the role it plays in flight. I worked with Dr. John Hermanson at Cornell University to study the histochemical properties of bat flight muscles in vampire bats.

Finally, I have been involved in several studies to map the motorneuron pools responsible for innervating the major flight muscle in bats and birds. We have found that the motorneuron pools for forelimb muscles are remarkably conserved by evolution. The relative location in the spinal cord of these clusters of neurons is essentially the same in terrestrial lizards, birds, mice, and bats regardless of the type of locomotion.

The maps above show the locations of the motor neuron clusters for various fore limb muscles in three representative vertebrates. The roman numerals indicate the level of the spinal nerves in each cross section of the spinal cord. The photos to the right show the actual motor nuerons for the pectoralis muscle in the little brown bat; the spinal cord was sectioned in the longitudinal plane (left photo) and in cross section (right photo).

For more information consult the following publications:

Hermanson, J.W., Ryan, J. M., Cobb, M.A., Bentley, J., and W.A. Schutt. 1998. Histochemical and electrophoretic analysis of the primary flight muscle of several phylostomid bats. Can. J. Zool., 76:1983-1992.

Sokoloff, A.J., Ryan, J.M., Valerie, E., Wilson, D.S., and G.E. Goslow, jr. 1998 Neuromuscular organization of avian flight muscle: Morphology and contractile properties of motor units in the pectoralis (pars thoracicus) of pigeon (Columba livia). J. Morph., 236:179-208.

Ryan, J.M., Cushman, J., Jordon, B., Samuels, A., Frazer, H., and C. Baier. 1998 Topographic position of forelimb motoneuron pools is conserved in vertebrate evolution, Brain, Behav., Evol., 51:90-99.

Ryan, J.M., J. Cushman, and C. Baier. 1997. Organization of forelimb motoneuron pools in two bat species (Eptesicus fuscus and Myotis lucifugus). Acta Anatomica, 158:121-129.

Authors in red are undergraduate co-authors.