JERNVALL, J.*; KER�NEN, S.V.E.; THESLEFF, I.: Quantifying evolutionary modification of development in mammalian molar topography Mammalian dentition is characterized by complex and diverse molar cusp patterns and subtle changes in molars are usually the earliest morphological evidence of modern orders in the fossil record. However, the exact ways that embryonic patterning of tooth shapes could […]
Archives: Abstracts
Ontogeny of the Extraembryonic Membranes in Oviparous Viviparous Lizards, Lacerta vivipara
STEWART, J.R.*; HEULIN, B.: Ontogeny of the Extraembryonic Membranes in Oviparous Viviparous Lizards, Lacerta vivipara. Lacerta vivipara is a reproductively bimodal species with allopatrically distributed viviparous and oviparous populations. Morphological, ecological and genetical similarities among populations indicate that oviparous and viviparous populations are closely related and diverged recently. This species provides a rare opportunity among […]
Neural-crest derivation of the ossified skull in amphibians revealed by vital labeling with GFP
CARL, T. F.; HANKEN, J.*: Neural-crest derivation of the ossified skull in amphibians revealed by vital labeling with GFP. Derivation of most if not all of the ossified skull from the embryonic neural crest is an accepted axiom of contemporary developmental biology. Yet, this “fact” is based on direct empirical results involving just one species […]
Cranial neural crest cell migration in the lamprey Petromyzon marinus
McCauley, D.W.*; Bronner-Fraser, M.: Cranial neural crest cell migration in the lamprey Petromyzon marinus The neural crest is a vertebrate-specific population of cells that gives rise to much of the peripheral nervous system, pigment cells, and many craniofacial derivatives including facial bones, cartilage, teeth, and cranial ganglia. We have begun to investigate the origin of […]
Ontogenetic expression of plunc, a mouse marker for selected derivatives of the pharyngeal epithelium
NGUYEN, L*; LECLAIR, E.E.: Ontogenetic expression of plunc, a mouse marker for selected derivatives of the pharyngeal epithelium. In mammalian development the lung and thymus both form from local expansions of the embryonic gut tube. The thymus arises from ventral elongations of the third pharyngeal pouch, while the lung tree starts as a ventral outpouching […]
Multiple functions for the gene Slug in Xenopus laevis
CARL, T.F.*; KLYMKOWSKY, M.W.; HANKEN, J.: Multiple functions for the gene Slug in Xenopus laevis The neural crest is a distinct population of embryonic cells found only in craniates. Several genes, including BMP-4and the zinc-finger transcription factor Slug, have been shown to mediate neural crest development in both chickens and mice. We examined the function […]
Morphological changes associated with the development of feeding in red snapper (Lutjanus campechanus)
Woodard, A.*; Shardo, J.: Morphological changes associated with the development of feeding in red snapper (Lutjanus campechanus). The formation of a functional feeding apparatus in larval teleosts is a finely tuned, functionally integrated set of processes. We examined the formation of the feeding apparatus in the larval red snapper from hatching (22 hr postfertilization) through […]
Heterochrony and patterns of osteogenesis in pelobatoid frogs
Maglia, A.*; Buchholz, D.R.: Heterochrony and patterns of osteogenesis in pelobatoid frogs Change in developmental timing is commonly cited as the source of morphological evolution in anurans (and vertebrates in general). Despite the warnings of Fink (1982), very few studies suggesting heterochrony as the cause of variation in anuran morphology have tested their hypotheses in […]
Diaphragm muscle development in bottlenose dolphins (Tursiops truncatus)
DEAROLF, J.L.*; MCLELLAN, W.A.; PABST, D.A.; HERMANSON, J.W.: Diaphragm muscle development in bottlenose dolphins (Tursiops truncatus) Being born directly into an aquatic environment creates unique challenges for the breathing muscles of neonatal cetaceans. Not only must these muscles be active at the instant of birth to allow for gas exchange, but their activities must also […]
Characterization of a novel Hox group gene 1 from Morone saxatilis
SMITH, M.H.; WILLIAMS, N.L.; STELLWAG, E.J.; SCEMAMA, J.L.*: Characterization of a novel Hox group gene 1 from Morone saxatilis Hox genes are transcription factors that control regional specification of tissues in developing embryos. Our laboratory is working toward the complete characterization of the Hox cluster genes from Morone saxitilis, a member of the order Perciformes. […]