Zoology Commons^™

Diffusion Tensor Imaging Of Dolphin Brains Reveals Direct Auditory Pathway To Temporal Lobe, Gregory S. Berns, Peter F. Cook, Sean Foxley, Saad Jbabdi, Karla L. Miller, Lori Marino

Lori Marino, Ph.D.

The brains of odontocetes (toothed whales) look grossly different from their terrestrial relatives. Because of their adaptation to the aquatic environment and their reliance on echolocation, the odontocetes’ auditory system is both unique and crucial to their survival. Yet, scant data exist about the functional organization of the cetacean auditory system. A predominant hypothesis is that the primary auditory cortex lies in the suprasylvian gyrus along the vertex of the hemispheres, with this position induced by expansion of ‘associative0 regions in lateral and caudal directions. However, the precise location of the auditory cortex and its connections are still unknown. Here, …

Two Tickets To Paradise: Multiple Dispersal Events In The Founding Of Hoary Bat Populations In Hawai'i, Amy L. Russell, Corinna A. Pinzari, Maarten J. Vonhof, Kevin J. Olival, Frank J. Bonaccorso

Amy L. Russell

The Evolutionary History Of Cetacean Brain And Body Size, Stephen H. Montgomery, Jonathan H. Geisler, Michael R. Mcgowen, Charlotte Fox, Lori Marino, John Gatesy

Lori Marino, PhD

Cetaceans rival primates in brain size relative to body size and include species with the largest brains and biggest bodies to have ever evolved. Cetaceans are remarkably diverse, varying in both phenotypes by several orders of magnitude, with notable differences between the two extant suborders, Mysticeti and Odontoceti.We analyzed the evolutionary history of brain and body mass, and relative brain size measured by the encephalization quotient (EQ), using a data set of extinct and extant taxa to capture temporal variation in the mode and direction of evolution. Our results suggest that cetacean brain and body mass evolved under strong directional …

New Records Of Merriam’S Shrew (Sorex Merriami) From Western North Dakota, Michael J. Shaughnessy Jr., Neal Woodman

Neal Woodman

Despite having a broad geographic distribution, Merriam’s Shrew (Sorex merriami Dobson 1890) is known from a relatively few, widely-scattered localities. In North Dakota, the species was known from only a single poorly-preserved specimen collected in 1913 near Medora. We recently collected two new specimens of Merriam’s Shrew from Billings and McKenzie counties in the western quarter of the state. These specimens confirm the presence of S. merriami in North Dakota and better define the northeastern edge of the species’ distribution.

The Global Decline Of Reptiles, Deja’ Vu Amphibians, J. Whitfield Gibbons, David E. Scott, Travis J. Ryan, Kurt A. Buhlmann, Tracey D. Tiuberville, Brian S. Metts, Judith L. Greene, Tony Mills, Yale Leiden, Sean Poppy, Christopher T. Winne

Travis J. Ryan

Reptile species are declining on a global scale. Six significant threats to reptile populations are habitat loss and degradation, introduced invasive species, environmental pollution, disease, unsustainable use, and global climate change.

Effects Of Hydroperiod On Metamorphosis In Rana Sphenocephala, Travis J. Ryan, Christopher T. Winne

Travis J. Ryan

Hydroperiod, the time a temporary pond holds water, is an important factor influencing recruitment in amphibian populations and structuring amphibian communities. We conducted an experiment to test the effect of hydroperiod on metamorphic traits of the southern leopard frog (Rana sphenocephala), a common amphibian in the southeastern United States. We reared larval R. sphenocephala in artificial ponds at a density of 32 larvae per tank (initial volume = approximately 650 liter). We dried the tanks according to natural patterns, using three different hydroperiods (60, 75 and 90 d). Experimental hydroperiods had a significant effect on the number of metamorphs and …

Intraspecific Heterochrony And Life History Evolution: Decoupling Somatic And Sexual Development In A Facultatively Paedomorphic Salamander, Travis J. Ryan, Raymond D. Semlitsch

Travis J. Ryan

Morphological features such as size and shape are the most common focus in studies of heterochronic change. Frequently, these easily observed and measured features are treated as a major target of selection, potentially ignoring traits more closely related to fitness. We question the primacy of morphological data in studies of heterochrony, and instead suggest that principal sources of fitness, such as life history characteristics, are not only the chief targets of selection, but changes in them may necessitate changes in other (subordinate) elements of the organism. We use an experimental approach to investigate the timing of metamorphosis and maturation in …

An Assessment Of South China Tiger Reintroduction Potential In Hupingshan And Houhe National Nature Reserves, China, Yiyuan Qin, Philip J. Nyhus, Courtney L. Larson, Charles J.W. Carroll, Jeff Muntifering, Thomas D. Dahmer, Lu Jun, Ronald L. Tilson

Philip J. Nyhus

Human-caused biodiversity loss is a global problem, large carnivores are particularly threatened, and the tiger (Panthera tigris) is among the world’s most endangered large carnivores. The South China tiger (Panthera tigris amoyensis) is the most critically endangered tiger subspecies and is considered functionally extinct in the wild. The government of China has expressed its intent to reintroduce a small population of South China tigers into a portion of their historic range as part of a larger goal to recover wild tiger populations in China. This would be the world’s first major tiger reintroduction program. A free-ranging population of 15–20 tigers …

Rafinesque’S Names For Western American Mammals, Including The Earliest Scientific Name For The Coyote (Canis Latrans Say, 1822), Based On The Apocryphal Journal Of Charles Le Raye, Neal Woodman

Neal Woodman

Variation In The Myosoricine Hand Skeleton And Its Implications For Locomotory Behavior (Eulipotyphla: Soricidae), Neal Woodman, Frank A. Stabile

Neal Woodman

Substrate use and locomotory behavior of mammals are typically reflected in external characteristics of the forefeet, such as the relative proportions of the digits and claws. Although skeletal anatomy of the forefeet can be more informative than external characters, skeletons remain rare in systematic collections. This is particularly true for the Myosoricinae (Eulipotyphla: Soricidae), a small clade of African shrews that includes both ambulatory forest shrews (Myosorex) and semifossorial mole shrews (Surdisorex). Most species in this subfamily have restricted distributions, and their behavior and ecology are mostly unstudied. To better understand the potential range of locomotory behavior among myosoricines, we …