| mammal and flea relationships in the great basin desert: from h. j. egoscue's collections. | host-parasite association among 58 flea species parasitizing 40 mammal species in the great basin desert of the western united states was investigated. increased flea species richness was correlated with larger geographic ranges and stable locomotion of hosts. hosts from habitats of moderately low productivity (sage and grass) and of peromyscus maniculatus size, 10-33 g, had the highest flea species richness. larger hosts had fewer flea species, but fleas were more prevalent. increased host spec ... | 2006 | 16729681 |
| ontogeny of the larynx and flight ability in jamaican fruit bats (phyllostomidae) with considerations for the evolution of echolocation. | echolocating bats have adaptations of the larynx such as hypertrophied intrinsic musculature and calcified or ossified cartilages to support sonar emission. we examined growth and development of the larynx relative to developing flight ability in jamaican fruit bats to assess how changes in sonar production are coordinated with the onset of flight during ontogeny as a window for understanding the evolutionary relationships between these systems. in addition, we compare the extent of laryngeal ca ... | 2014 | 24778087 |
| morphological and molecular differentiation of staphylocystis clydesengeri n. sp. (cestoda, hymenolepididae) from the vagrant shrew, sorex vagrans (soricomorpha, soricidae), in north america. | staphylocystis clydesengeri n. sp. is described from shrews sorex vagrans in montana and washington, united states. it differs from the only previously known north american representative of the genus, s. schilleri, in having more numerous (37-42 vs. 22-30) and larger (39-44 microm vs. 27-30 microm) rostellar hooks. the two species also differ in several other important characters such as relative length of the cirrus pouch, position of gonads and shape of mature proglottides. morphological diff ... | 2013 | 26167593 |
| tripartite genetic subdivisions in the ornate shrew (sorex ornatus). | we examined cytochrome b sequence variation in 251 ornate shrews (sorex ornatus) from 20 localities distributed throughout their geographical range. additionally, vagrant (s. vagrans) and montane (s. monticolus) shrews from four localities were used as outgroups. we found 24 haplotypes in ornate shrews from california (usa) and baja california (mexico) that differed by 1-31 substitutions in 392 bp of mitochondrial dna (mtdna) sequence. in a subset of individuals, we sequenced 699 bp of cytochrom ... | 2001 | 11251793 |
| shrew metabolic rates and thyroxine utilization. | elevated basal metabolic rates (bmr) in shrews have been observed for over 40 years, yet no one has investigated the physiological basis for this phenomenon. this paper reports on investigations of thyroid function in a shrew (sorex vagrans), and in three rodent species for comparison. the utilization rate of thyroxine in shrews is found to be much higher than for any of the rodents, and is correlated with bmr expressed as a percentage of the predicted bmr. it is concluded that the unusually hig ... | 1984 | 6147226 |