Browsing by Author "Van Gelder, Richard George, 1928-"
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Item The genus Conepatus (Mammalia, Mustelidae) : variation within a population. American Museum novitates ; no. 2322(New York, N.Y. : American Museum of Natural History, 1968) Van Gelder, Richard George, 1928-; Kipp, Hilde."One hundred three specimens of the genus Conepatus from Uruguay have been analyzed for age, sex, and individual variation of both skins and skulls. Sexual dimorphism in the cranial measurements is sufficiently great to preclude consideration of both sexes as a single unit in systematc studies. Similarly, there are significant differences between age groups of the same sex great enough to indicate that taxonomic comparisons must be made between individuals of comparable age. Individual variation in cranial dimensions is sufficiently low (coefficient of variation less than 5) in about 10 measurements to suggest that these will be most useful taxonomic criteria. An analysis of color pattern indicates considerable individual variation but no sex or age differences. From the material available, no conclusions about molt or seasonal variation could be made. Kipp (1965) is the only other person who has investigated variation in this genus in detail. Her sample consisted of 84 specimens, of which only 26 were skins with associated skulls. The total sample was drawn from an area larger than 600,000 square miles, with varied topography and climate. Although she called specimens adult, subadult, and juvenile, Kipp did not present data for age criteria, and some of the questions she raised indicate that she did not refine her age categories sufficiently. Her comments (pp. 218-219) on postorbital breadth and zygomatic breadth seem to indicate that she did not recognize these as age characters. In drawing her taxonomic conclusions, she relied almost entirely on characters of the skins. Her placement of Uruguayan material (Kipp, 1965, map p. 226) in the group of skunks having bicolored hair in the tail is not correct. This paper presents the basic analyses that will permit a more objective evaluation of characters used in the classification of the genus Conepatus"--P.33-35.Item Mammalian hybrids and generic limits. American Museum novitates ; no. 2635(New York, N.Y. : American Museum of Natural History, 1977) Van Gelder, Richard George, 1928-"A taxonomic level, the genus, is analyzed from the perspective of reproduction isolation. It is concluded that if species are, by definition, reproductively isolated, then species in one genus should not be capable of breeding with species in other genera. A survey of reported mammalian intergeneric intergeneric hybrids and the application of reproductive criteria to the definition of the category of genus led to the recommendation of a number of taxonomic changes in the context of genera. These include the following genera, with synonyms in parentheses: Macropus (Thylogale, Osphranter, Megaleia, Wallabia); Cercopithecus (Papio, Macaca, Cercocebus, Mandrillus, Cynopithecus, Theropithecus, Erythrocebus, Allenopithecus, Comopithecus); Grampus (Steno, Tursiops); Canis (Alopex, Urocyon, Fennecus, Vulpes, Cerdocyon, Dusicyon); Ursus (Thalarctos, Selenarctos); Melursus (Helarctos); Felis (Panthera); Arctocephalus (Zalophus); Tayassu (Dicotyles); Cervus (Dama, Axis, Elaphurus); Bos (Bibos, Bison); Tragelaphus (Taurotragus, Boocercus); Cephalophus (Sylvicapra); Alcelaphu (Damaliscus, Beatragus); Connochaetes (Gorgon); Kobus (Adenota, Onotragus); Capra (Ovis, Ammotragus)"--P. [1].Item The natural history of nyala, Tragelaphus angasi (Mammalia, Bovidae) in Mozambique. Bulletin of the AMNH ; v. 155, article 4(New York : American Museum of Natural History, 1975) Tello, José L. P. Lobão.; Van Gelder, Richard George, 1928-"We made observations of nyala (Tragelaphus angasi) for more than 2000 man-hours primarily between September, 1971, and April, 1974, in Zinave National park, Mozambique, and vicinity, mostly in a study area of approximately 32 sq. km., near Zinave Camp on the Save River. Data on habitat, climate, measurements, and age and growth of nyala are presented. In the study area 70 percent of the adults seen were females. The population of nyala in the study area increased from an estimated 175 to 250 in 1971 to more than 326 in 1973, for a density of about 10 nyala per sq. km. More than 60 percent of the nyala seen were adults. Nyala were seen alone or in groups up to 30 in number; 67 percent of the observations were of one to three animals. Males were seen alone twice as frequently as females. Nyala groups are not permanent, and individuals come and go. A subadult male was seen in association with at least 15 other individuals and an immature with 16 in eight and 13 days respectively. The strongest bond is probably between a mother and her young, but newborn nyala are left hidden in thickets for several weeks. The home range of male nyala is up to 10 sq. km., and does not change seasonally. The home range of females is approximately the same size. No evidence of territoriality has been observed, and there is extensive overlap of home ranges of males and females. Nyala are active in the daytime especially at temperatures between 20° C. and 30° C. and at night during the rainy season. They shelter from both sun and cold in thickets and at Zinave drink daily. In the dry season when food is less available nyala may wander 12 km. between sunup and sundown. Lions and leopards are the main predators of adult nyala, whereas baboons and raptorial birds are the principal predators of juveniles. Nyala are killed by man for trophies and meat. Nyala have a single offspring born after an eight and one-half month gestation period at any time of the year. Females may conceive within a week after parturition. Nyala are often seen in association with impala or baboons. Nyala eat leaves, fruits, flowers, twigs, and bark of more than a hundred species of plants. They are parasitized by ticks, flies, trypanosomes, and helminths. The social behavior of nyala is shown mainly by male displays and rituals for assertion of dominance without fighting. A hypothesis of the communicatory role of the white markings of nyala is presented"--P. 323.Item Results of the Puritan-American Museum of Natural History Expedition to Western Mexico. 10, Marine mammals from the coasts of Baja California and the Tres Marías Islands, Mexico. American Museum novitates ; no. 1992(New York, N.Y. : American Museum of Natural History, 1960) Van Gelder, Richard George, 1928-; Puritan-American Museum of Natural History Expedition to Western Mexico (1957)Item Results of the Puritan-American Museum of Natural History Expedition to Western Mexico. 8, A new Antrozous (Mammalia, Vespertilionidae) from the Tres Marías Islands, Nayarit, Mexico. American Museum novitates ; no. 1973(New York, N.Y. : American Museum of Natural History, 1959) Van Gelder, Richard George, 1928-; Zweifel, Richard George, 1926-; Plimpton, Oakes.; Puritan-American Museum of Natural History Expedition to Western Mexico (1957)Item A review of canid classification. American Museum novitates ; no. 2646(New York, N.Y. : American Museum of Natural History, 1978) Van Gelder, Richard George, 1928-"A review of the varied classifications of Recent members of the family Canidae involving morphological, numerical, and reproductive analyses suggests that the taxonomy should be arranged with six monotypic genera (Chrysocyon, Speothos, Nyctereutes, Cuon, Lycaon, and Otocyon), and one polytypic genus, Canis, with eight subgenera (Canis, Dusicyon, Pseudalopex, Lycalopex, Cerdocyon, Atelocynus, Vulpes, and Alopex)"--P. [1].Item A taxonomic revision of the spotted skunks (genus Spilogale). Bulletin of the AMNH ; v. 117, article 5(New York : [American Museum of Natural History], 1959) Van Gelder, Richard George, 1928-"The spotted skunks (genus Spilogale), which were last revised by Arthur H. Howell in 1906, are restudied on the basis of 1974 musuem specimens. Analyses of the distribution, the age, sex, color pattern, and individual variation, the probable prehistory, and the evolutionary trends of spotted skunks are presented. The taxa of the genus are arranged in two species: Spilogale putorius, a large-sized, polytypic species of wide distribution, and Spilogale pygmaea, a monotypic species, small-sized, with a restricted range. The differences between the two species and between the subspecies of Spilogale putorius are mainly those of size and color pattern"--P. 390.Item The taxonomy and status of bats in Bermuda. American Museum novitates ; no. 2029(New York, N.Y. : American Museum of Natural History, 1961) Van Gelder, Richard George, 1928-; Wingate, David B.