摘要:

Adult static intraspecific allometry of tooth size was evaluated in a sample of 66Otolemur crassicaudatus(34 male, 32 female). Tooth areas were calculated from mesiodistal and buccolingual measurements of canines and postcanine teeth of both arcades and were scaled to four viscerocranial measurements: bimaxillary width; maxillo‐alveolar length; mandibular length and bigonial width. Individual tooth crown areas were also scaled to total skull length, body length and body weight. From the log‐transformed analyses it is concluded that postcanine tooth size was unrelated to body length or weight, and poorly correlated to skull length or jaw size. Although viscerocranial size appears to be independent of body size, these measures are well correlated to skull length. It is shown that the longer the skull, the shorter and narrower the maxilla, and the longer and broader the mandible. Canines are shown to scale negatively allometric to skull length, hence, large animals will have relatively small cani

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1990.tb01203.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Quantitative and qualitative analyses of filming studies reveal that fundamental differences exist between the gaits of the New Zealand fur seal (Arctocephalus forsteri) and the Hooker's sea lion (Phocarctos hookeri). Terrestrial locomotion of the latter species is similar to that of terrestrial vertebrates in which the limbs are moved in sequence, alternately and independently. In contrast, the gait of the New Zealand fur seal does not conform to this sequence, the hind limbs being moved in unison. The gaits of both species are defined and illustrated. The limbs of otariids are structurally adapted for a semi‐aquatic lifestyle and consequently large oscillations of the centre of gravity are necessary to enable the limbs to be lifted and protracted during terrestrial locomotion.Phocarctos hookeriachieves this by transferring weight in the transverse plane while inA.forsteriit is in the sagittal plane. Hind limb movements are distinctly different;P. hookerimoves each hind limb individually by the combined action of limb protraction and rotation of the pelvis whileA. forsterimoves its hind limbs together, predominantly by flexion of the posterior axial skeleton. While terrestrial locomotion in these species is achieved by fundamentally different gaits, post cranial elements ofA. forsteriandP. hookeriare barely distinguishable; selection for the behavioural control of terrestrial locomotion has apparently preceded structural modifications. The gaits are considered to be ecological specializations which are adaptations to the mechanical problems imposed by different habitats. Gaits of these species appear typical or representative of members of their inferred subfamilies (Arctocephalinae and Otariinae). The gaits ofA. forsteriandP. hookeriare however paradoxical in light of their inferred evolutionary history since the gait of the Hooker's sea lion resembles more closely that of the putative ancestors of otariids (arctoid fissiped carnivores) than does the gait of the supposedly more primitive New Zealand fur sea

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1990.tb01204.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Zodariid spiders of two genera in Israel are revised. The genusLachesanais represented by two species. Only one male of these was ever depicted while the females of both and their hitherto unknown retreats were never described.Paxgen. nov.has been erected to accommodate five species, some of which have formerly been placed inSlorena, SelamiaorHabronestes. Diagnostic characters of the West MediterraneanSelamiaand the AustralianHabronestesare newly illustrated. No drawings ofPax libaniandP. islamitawere ever published; the male of the latter is described here for the first time.Pax palmoniisp. nov.andP. engediensissp. nov.are described and affinities of all taxa are discussed. Illustrations, records of distribution and keys to the species are provided.

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1990.tb01205.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Material of the Miocene hyaenidAdcrocuta eximiafrom China is analysed statistically. No heterogeneities were found within this material. Comparisons with material from Samos and Pikermi, Greece, show that no taxonomic differentiation between these three samples is warranted.Adcrocuta eximia latrofrom the Sivalik deposits is provisionally considered a valid subspecies. The speciesA. australisfrom Langebaanweg, South Africa is removed fromAdcrocutato the genusChasmaporthetes. The phylogenetic position ofAdcrocutahas been subject to dispute, and for this reason we present a study of the interrelationships of selected hyaenid taxa using numerical cladistic methods. Two equally parsimonious trees of length 47 and consistency index 0.766 were found.Adcrocutais placed as a sister‐group to the RecentCrocuta crocuta, and not as a separate clade as suggested by other workers. Recent hyaenids form a crown‐group which does not extend deep into the cladogram.Hyaena hyaenaandH. brunneaare not sister‐groups, and we resurrect the genusParahyaenafor the latter sp

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1990.tb01206.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY