American Zoologist articles from June 1999

American Zoologist archives from June 1999

Contributions of Dorothy M. Skinner to the Development of Crustacean Biology(1).
June 1, 1999... INTRODUCTION This symposium was the most recent in an occasional ASZ-SICB mini-series honoring crustaceans and crustacean biologists. The first in this series, the Symposium on Terrestrial Adaptations in Crustacea, organized by Dorothy...

Toward an Understanding of Satellite DNA Function in Crustacea(1).
June 1, 1999... INTRODUCTION Repetitive DNAs are widely distributed among eukaryotes. The repeats vary in complexity from simple oligonucleotides to complex sequences of several kilobases. When repeats with G+C or A+T contents significantly different...

Quantification of Stress in Lobsters: Crustacean Hyperglycemic Hormone, Stress Proteins, and Gene Expression(1).
June 1, 1999... INTRODUCTION Observations that eyestalk factors may regulate blood glucose concentrations in crustaceans were made several decades ago by Abramowitz et al. (1944). They found that injected eyestalk extracts were able to elevate the blood...

Signaling Pathways for Ecdysteroid Hormone Synthesis in Crustacean Y-organs(1).
June 1, 1999... INTRODUCTION In crustaceans, a pair of epithelioid glands (Y-organs) secrete steroid hormones (ecdysteroids). The hormones control molting/growth cycles which represent post-embryonic development including regeneration of body parts as...

Limb Regeneration in the Fiddler Crab, Uca pugilator: Histological, Physiological and Molecular Considerations(1).
June 1, 1999... GROWTH AND REGENERATION Of the many contributions that Dorothy Skinner has made to the study of crustaceans, the work she has done on the interactions of molting and regeneration deserves special attention. Her work in this area involves...

Muscle Restructuring in Crustaceans: Myofiber Death, Transfiguration and Rebirth(1).
June 1, 1999... Alpheid shrimps are quasi-social crustaceans that defend territories from conspecifics and that prey on smaller invertebrates. To these ends they have evolved a unique offensive and defensive weapon: one of their chelipeds, referred to as the...

Proteolytic Processes Underlying Molt-Induced Claw Muscle Atrophy in Decapod Crustaceans(1).
June 1, 1999... INTRODUCTION The mechanical problem of pulling out the large distally-enlarged chelipeds of decapod crustaceans at molting was widely recognized by 19th century biologists (see Mykles and Skinner, 1990; Skinner and Cook, 1991; Mykles,...

[Ca.sup.2+]-Activated Force Production and Calcium Handling by the Sarcoplasmic Reticulum of Crustacean Muscles During Molt-Induced Atrophy(1).
June 1, 1999... INTRODUCTION Growth in crustaceans is an intermittent process centered around the principal event of ecdysis. Ecdysis is an event in the molt cycle when the old exoskeleton is shed to accommodate an increase in the size of the...

Regulation of Muscle Growth and Sarcomeric Protein Gene Expression over the Intermolt Cycle(1).
June 1, 1999... INTRODUCTION Pioneering work by Dorothy Skinner and colleagues first began to consider changes in muscle mass through the molt cycle in the claws of the land crab, Gecarcinus lateralis, in the mid 60s (Skinner, 1965, 1966). Our work has...

Limb Autotomy as an Investigatory Tool: Host Molt-Stage Affects the Success Rate of Infective Larvae of a Rhizocephalan Barnacle(1).
June 1, 1999... INTRODUCTION Zeleny (1905) reported that crayfish missing two chelipeds molted sooner than those lacking one. The significance of this observation was not realized by carcinologists until 50 years later when Dorothy Skinner, working as a...

Hemolymph Proteins and Molting in Crustaceans and Insects(1).
June 1, 1999... INTRODUCTION Synthesis and hardening of a new exoskeleton are essential parts of arthropod growth and molting. In both crustaceans and insects, the hardening of the newly formed exoskeleton or cuticle is referred to as sclerotization....

Cuticular Proteins in Insects and Crustaceans(1).
June 1, 1999... INTRODUCTION The Biological Laboratories at Harvard University in the late 1950s was a genteel place, where, before departmental seminars, the women graduate students (officially registered at Radcliffe) brewed and served tea from a...

A Tribute to Dorothy Skinner: A Complete Person(1).
June 1, 1999... All other considerations aside, I want you to know that I have asked myself, "What am I doing here addressing a gaggle of crustacean biologists?" Then I began to remember that I really enjoy all of endocrinology, never paid much heed to the...

Introduction to the Symposium: Developmental and Evolutionary Perspectives on Major Transformations in Body Organization(1).
June 1, 1999... Any comprehensive theory of organismal form must relate the short-term processes of embryonic development to the long-term processes of evolutionary change--in what Mayr (1982, 1994, 1997) termed "internal" and "external" biology; see Mayr...

The Origin of Bodyplans(1).
June 1, 1999... INTRODUCTION George Gaylord Simpson began Tempo and Mode in Evolution, his magnificent contribution to evolution's modern synthesis, with the following words: "How fast, as a matter of fact, do animals evolve in nature? That is the...

Amphioxus and the Utility of Molecular Genetic Data for Hypothesizing Body Part Homologies between Distantly Related Animals(1).
June 1, 1999... INTRODUCTION In 1830, there was a famous debate between Geoffroy Saint-Hilaire, who dared to propose body part homologies over a wide spectrum of animals, and Cuvier, who thought such homologies should be made only between very closely...

The Evolution of Dorsoventral Pattern Formation in the Chordate Neural Tube(1).
June 1, 1999... INTRODUCTION Vertebrates share Phylum Chordata with two other living taxa, the Urochordata (ascidians and relatives) and the Cephalochordata (amphioxus), known collectively as the protochordates. These taxa are united by the possession...

Out on a Limb: Parallels in Vertebrate and Invertebrate Limb Patterning and the Origin of Appendages(1).
June 1, 1999... INTRODUCTION One of the most profound impacts of the last decade of research in developmental biology has been the realization that a large number of analogous processes in Drosophila and model vertebrates are regulated by homologous...

Morphogenesis and Homology in Arthropod Limbs(1).
June 1, 1999... DEFINING HOMOLOGIES BETWEEN ARTHROPOD LIMBS One exciting finding of the last few decades has been the widespread conservation of patterning genes in diverse groups of organisms. Hox genes, which play an important role in patterning the...

Vertebrate Axial and Appendicular Patterning: The Early Development of Paired Appendages(1).
June 1, 1999... INTRODUCTION This article summarises (and updates) a recent synthesis of palaeontological and developmental perspectives on vertebrate postcranial skeletal patterning (Coates and Cohn, 1998), which re-examines major evolutionary changes...

Evolution of Hoxa-11 Expression in Amphibians: Is the Urodele Autopodium an Innovation?
June 1, 1999... INTRODUCTION It has been known for more than a century that urodele limb development is different from that of other tetrapods (for a review see Shubin and Alberch [1986]). This knowledge has been used to propose a polyphyletic origin...

Foraging for Survival: Yearling Baboons in Africa.(Review)
June 1, 1999... Foraging for Survival: Yearling Baboons in Africa. STUART A. ALTMANN. The University of Chicago Press, Chicago, 1998, xii + 608 pp., cloth $70. (ISBN 0-226-01595-5.) I have not so much reviewed this book as studied it carefully, it is so...

Monitoring Vertebrate Populations.(Review)
June 1, 1999... Monitoring Vertebrate Populations. WILLIAM L. THOMPSON, GARY C. WHITE, AND CHARLES GOWAN. Academic Press, 1998, 365 pp. (ISBN No. 0-12-688960-0, $64.95.) In a world where human societies are exerting increasing pressures on wildlife...

Animal Vocal Communication: A New Approach.(Review)
June 1, 1999... Animal Vocal Communication: A New Approach. DONALD H. OWINGS AND EUGENE S. MORTON. Cambridge University Press, New York, 1998. xii + 284 pp., illus., index. (ISBN 0-521-32468-8 hardback, $64.95.) Scientists who study animal communication...