Abstract:
:The extravagance and diversity of external genitalia have been well characterized in male primates; however, much less is known about sex differences or variation in female form. Our study represents a departure from traditional investigations of primate reproductive anatomy because we 1) focus on external rather than internal genitalia, 2) measure both male and female structures, and 3) examine a strepsirrhine rather than an anthropoid primate. The subjects for morphological study were 21 reproductively intact, adult ring-tailed lemurs (Lemur catta), including 10 females and 11 males, two of which (one per sex) subsequently died of natural causes and also served as specimens for gross anatomical dissection. Male external genitalia presented a typical masculine configuration, with a complex distal penile morphology. In contrast, females were unusual among mammals, presenting an enlarged, pendulous external clitoris, tunneled by the urethra. Females had a shorter anogenital distance and a larger urethral meatus than did males, but organ diameter and circumference showed no sex differences. Dissection confirmed these characterizations. Noteworthy in the male were the presence of a "levator penis" muscle and discontinuity in the corpus spongiosum along the penile shaft; noteworthy in the female were an elongated clitoral shaft and glans clitoridis. The female urethra, while incorporated within the clitoral body, was not surrounded by erectile tissue, as we detected no corpus spongiosum. The os clitoridis was 43% the length and 24% the height of the os penis. On the basis of these first detailed descriptions of strepsirrhine external genitalia (for either sex), we characterize those of the female ring-tailed lemur as moderately "masculinized." Our results highlight certain morphological similarities and differences between ring-tailed lemurs and the most male-like of female mammals, the spotted hyena (Crocuta crocuta), and call attention to a potential hormonal mechanism of "masculinization" in female lemur development.
journal_name
J Morpholjournal_title
Journal of morphologyauthors
Drea CM,Weil Adoi
10.1002/jmor.10594subject
Has Abstractpub_date
2008-04-01 00:00:00pages
451-63issue
4eissn
0362-2525issn
1097-4687journal_volume
269pub_type
杂志文章abstract::A hitherto unknown sensillum type, the "intracuticular sensillum" was identified on the dactyls of the walking legs of the shore crab, Carcinus maenas. Each sensillum is innervated by two sensory cells with dendrites of "scolopidial" (type I) organization. The ciliary segment of the dendrite is 5-6 μm long and contain...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052040311
更新日期:1990-06-01 00:00:00
abstract::The vascular system of the digits of the tokay is more complex than has hitherto been suspected and has a configuration which suggests it is intimately involved in the process of adhesion. Distinction can be made between lamellae (expanded scales beneath the proximal portion of the digit) and scansors (elaborations of...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051690305
更新日期:1981-09-01 00:00:00
abstract::Development of the yolk sac of squamate reptiles (lizards and snakes) differs from other amniote lineages in the pattern of growth of extraembryonic mesoderm, which produces a cavity, the yolk cleft, within the yolk. The structure of the yolk cleft and the accompanying isolated yolk mass influence development of the a...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20052
更新日期:2012-10-01 00:00:00
abstract::Bone is a dynamic tissue adapting to loading according to "Wolff's law of bone adaptation." During very early life, however, such a mechanism may not be adequate enough to adapt to the dramatic change in environmental challenges in precocial species. Their neonates are required to stand and walk within hours after bir...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20548
更新日期:2016-07-01 00:00:00
abstract::Head structures of the leaf mining larva of the chrysomelid species Podagricomela shirahatai are described and illustrated. Internal and external structures were reconstructed three dimensionally based on image stacks obtained with microcomputed tomography. The larval head is characterized by prognathism, a dorsoventr...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20352
更新日期:2015-04-01 00:00:00
abstract::Barnacle cypris larvae show high morphological variation in the organs used in search of and attaching to a substratum. This variation may represent adaptation to the habitat of the species. Here, we studied SEM level morphologies of cypris antennular sensory and attachment organs in a deep-sea vent endemic species (N...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20522
更新日期:2016-05-01 00:00:00
abstract::The Eurasian lynx (Lynx lynx) is a medium-sized felid, with a tendency to hunt for prey larger than itself. We studied the lynx hindlimb musculoskeletal anatomy in order to determine possible anatomical adaptations to hunting large prey. In our previous work, we had found characters of both large and small felids in t...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.21328
更新日期:2021-01-25 00:00:00
abstract::The egg tooth of squamates evolved to facilitate hatching from mineralized eggshells. Squamate reptiles can assist their hatching with a single unpaired egg tooth (unidentates) or double egg teeth (geckos and dibamids). Egg tooth ontogeny in two gekkotan species, the leopard gecko Eublepharis macularius and the mourni...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.21249
更新日期:2020-10-01 00:00:00
abstract::Sensory epithelia of the oral tube, a fungiform body anterior to the tentacles and of the terminal knob of tentacles, were studied in Ovatella myosotis by electron microscopy. All three epithelia consist of columnar support cells, sensory cells, and, except in the oral tube, numerous goblet cells. The epithelia differ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051810307
更新日期:1984-09-01 00:00:00
abstract::Swimming crabs of the taxon Portunoidea show specialized, paddle-shaped fifth pereiopods (P5), which play a role in these crabs' ability to swim. In this study, the morphology of the fifth pereiopod in swimming and non-swimming crabs was studied in detail and the mobility in the articulations between podomeres was cal...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.21268
更新日期:2020-12-01 00:00:00
abstract::Sexual dimorphism in the distribution of antennal sense organs is common among adults of the genus Periplaneta. In three out of the four strains of Periplaneta americana examined, adult males had more contact chemoreceptros than females. In the fourth strain of P. americana and in P. australasiae, P. brunnea, P. fulig...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051490202
更新日期:1976-06-01 00:00:00
abstract::The results of an ultrastructural investigation of the gastric glands of the ruin lizard are reported. In this reptile the stomach can be divided into a larger fundus and a smaller pars pilorica. Fundic glands are characterized by three main kinds of cells: mucous, endocrine, and oxynticopeptic; the latter were not ob...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(200002)243:2<167::AID-JMOR
更新日期:2000-02-01 00:00:00
abstract::The progression of ovarian follicular development in the Northern Alligator Lizard has been documented ultrastructurally and by enumeration of cells, with a focus on changes in the granulosa component of the follicle. The pattern of cellular differentiation of the granulosa entails, as in other lizards, the transforma...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051920205
更新日期:1987-05-01 00:00:00
abstract::According to the current opinion, lymph-heart striated muscle represents a specialized type of skeletal muscles in frogs. Here, we studied muscle fibers in mechanically damaged lymph hearts during the first postoperative week using electron-microscopic autoradiography. We present evidence that both, the satellite cell...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20476
更新日期:2015-12-01 00:00:00
abstract::The king-of-the-salmon, Trachipterus altivelis (Lampriformes), has an unusual set of oral jaws which allow it the ability to protrude the entire upper jaw, containing the premaxilla and the maxilla bones, to extreme distances. Here, we provide a short description of the cranial anatomy and mechanism of jaw protrusion ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.21071
更新日期:2019-12-01 00:00:00
abstract::The microvasculariaztion of the lateral line organs (LLOs) of the adult pipid frog, Xenopus laevis was studied by scanning electron microscopy of vascular corrosion casts (VCCs) and correlative light microscopy of paraplast embedded tissues sections. Scanning electron micrographs of VCCs revealed that each neuromast w...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20232
更新日期:2014-05-01 00:00:00
abstract::The plainfin midshipman fish Porichthys notatus has both inter- and intra-sexual dimorphism in the sound-producing (vocal or sonic) muscles attached to the swimbladder wall. The "Type I" and "Type II" male morphs differ in that dramatic structural changes related to sexual maturity occur in the mass, the area of mitoc...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052160306
更新日期:1993-06-01 00:00:00
abstract::Bats are distributed worldwide from tropical to temperate regions. Despite their wide geographical radiation and advances in studies using evolutionary approaches, aspects related to the reproduction of these animals remain poorly explored, especially those related to the male reproductive accessory glands (RAGs). Thu...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20767
更新日期:2018-02-01 00:00:00
abstract::After placing in vitro, central subgerminal ooplasm (containing a central nucleus of Pander) from a quail germ disc of a prelaid egg (before symmetrization) on the upper layer of an isolated chicken antisickle, we observed the induction of a radially oriented preneural plate (without interference of chordamesoblast). ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10203
更新日期:2004-05-01 00:00:00
abstract::To date, the phylum Cycliophora comprises only one described extant species of acoelomate marine invertebrates, Symbion pandora. Adult specimens live commensally on the mouthparts of the Norwegian lobster, Nephrops norvegicus. Its complicated life cycle includes an asexually produced Pandora larva and a sexually produ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10354
更新日期:2005-08-01 00:00:00
abstract::Stauromedusae have relatively few macromorphological characters, making both their taxonomy and identification difficult. For this reason, histological characters are also employed in the taxonomy of the group. This study presents a detailed description of the histomorphology of Haliclystus antarcticus Pfeffer, 1889 (...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20185
更新日期:2013-12-01 00:00:00
abstract::The identity and taxonomic distribution of paranasal sinuses among living platyrrhines has remained a contentious issue (e.g., Cave [1967] Am J Phys Anthropol 26:277-288 vs. Hershkovitz [1977] Chicago: University of Chicago Press) largely because the ontogenetic data required for their detection and identification (e....
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10263
更新日期:2006-01-01 00:00:00
abstract::We investigated growth-related and sex-related morphological changes in the skulls of 144 North Pacific common minke whales Balaenoptera acutorostrata. Measurement was conducted at 39 points on the skull and mandible to extract individual allometric equations relating the length and zygomatic width of the skull. The r...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20288
更新日期:2014-10-01 00:00:00
abstract::The neuromuscular control of the hind limb of helmeted guineafowl (Numida meleagris) locomoting on a treadmill at 1.0 m/sec was analyzed using simultaneous electromyography (EMG) and cineradiography. Activity from 16 heads representing 14 hip and knee muscles was recorded and correlated with limb movement and myologic...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199905)240:2<127::AID-JMOR
更新日期:1999-05-01 00:00:00
abstract::Two types of sperm are produced in the silkworm, Bombyx mori. Nucleate eupyrene sperm is an ordinary sperm that contributes to fertilization, while anucleate apyrene sperm is considered to play important roles in assisting eupyrene sperm. At the very late stage of spermatogenesis, a phenomenon called "peristaltic sque...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10168
更新日期:2004-01-01 00:00:00
abstract::Topological and histological analyses of Mabuya mabouya embryos at different developmental stages showed an extraembryonic membrane sequence as follows: a bilaminar omphalopleure and progressive mesodermal expansion around the whole yolk sac at gastrula stages; mesodermal split and formation of an exocoelom in the ent...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10138
更新日期:2003-11-01 00:00:00
abstract::The forelimbs, along with the crania, are an essential part of the prey-killing apparatus in cats. Linear morphometrics of the forelimbs were used to determine the morphological differences between felids that specialize on large prey, small prey, or mixed prey. We also compared the scaling of felid forelimbs to those...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10712
更新日期:2009-06-01 00:00:00
abstract::Large pinnae are characteristic of the Leporids, and the pinna is known to have a thermoregulatory role. Another role has been hypothesized for the pinna of Lepus spp., as a part of a suspensory system for the greater portion of the head, absorbing shock that might otherwise interfere with vision during high-speed loc...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10825
更新日期:2010-06-01 00:00:00
abstract::The stomach of decapods is a complex organ with specialized structures that are delimited by a cuticle. The morphology and ontogeny of the stomach are largely described, but few studies have focused on the morphology of its cuticle. This study examined the morphology of the stomach cuticle of cardiac sacs, gastric mil...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20949
更新日期:2019-03-01 00:00:00
abstract::Fine structural changes in mitochondrial morphology pertaining to size, number and growth were examined in flight muscles of normal and experimentally dewinged male Drosophila melanogaster ranging up to 26 days of age. In the normal winged flies, the number of mitochondria decreases during the first week of adult lif...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051450307
更新日期:1975-03-01 00:00:00