American Zoologist articles from September 1998

American Zoologist archives from September 1998

The development of cooperative associations between animals and bacteria: establishing detente among domains.
September 1, 1998... INTRODUCTION Biologists have long known that animal evolution, including the evolution of their developmental pathways, occurred in environments ecologically dominated by bacteria. The members of the Domain Bacteria preceded the...

Developmental gene regulation adn the evolution of large animal body plans.
September 1, 1998... INTRODUCTION One of the most exciting and fundamentally important discoveries of paleontology is that remains of many animal phyla appear in the fossil record almost at once, during the geological period known as the Cambrian. The...

Evolutionary modifications of the spiralian developmental program.
September 1, 1998... INTRODUCTION In 1994 the journal Science conducted a survey among 100 leading developmental biologists asking them to identify the most important unanswered questions in their field. Number 2 on the list was the relation between...

Hox genes and segmental patterning of the vertebrate hindbrain.
September 1, 1998... INTRODUCTION The hindbrain provides a tractable model system for the study of axial patterning mechanisms in vertebrates. The developing hindbrain is transiently subdivided along the rostro-caudal axis into a series of reiterated...

Evolution of vertebrate limbs: robust morphology and flexible development.
September 1, 1998... RELATIONSHIP BETWEEN MORPHOLOGY AND DEVELOPMENT Knowledge of embryological development is critical to understanding the evolution of diverse body plans. Classically, studies of comparative embryology contributed significantly to the...

The development of radial and biradial symmetry: The evolution of bilaterality.
September 1, 1998... INTRODUCTION Recent reports indicate that there is surprising conservation in the cellular and molecular basis of embryonic patterning events in organisms as diverse as mice and insects. One can only wonder how deeply rooted these...

Evolution of eye regression in the cavefish Astyannax: Apoptosis and the Pax-6 gene.
September 1, 1998... "As it is difficult to imagine that eyes, though useless, could be in any way injurious to animals living in darkness, I attribute their loss wholly to disuse". Charles Darwin (1859) The Origin of Species INTRODUCTION Cave animals...

Muscle function in vivo: A comparison of muscles used for elastic energy savings versus muscles used to generate mechanical power.
September 1, 1998... Muscles generate the forces needed to produce and control the movement of animals. In the process of doing so, muscles may shorten to produce power by performing mechanical work, absorb energy by lengthening to do negative work, or generate...

The control of mechanical power in insect flight.
September 1, 1998... INTRODUCTION Matching power production and power requirements In order to move, animals use muscles and cilia to do work on the external world. In doing so, there must be a match between the work required for locomotion and the...

Elements of style in neuromuscular architecture.
September 1, 1998... INTRODUCTION The study of muscular organization, long the province of the anatomist, has attracted much broader interest over the past ten years. This interest has been driven at least in part by an unlikely force--the technological...

Post-activation potentiation - a clue for simplifying models fo muscle dynamics.
September 1, 1998... INTRODUCTION Studies of the neural control of movement generally tend to ignore muscle and its properties, but recent work has suggested that the intrinsic properties of muscle may have large effects on the control problem (Loeb et...

Muscle dynamics in fish during steady swimming.
September 1, 1998... INTRODUCTION Undulatory swimming in fish involves the coordinated activation and contraction of lateral myotomes alternately down each side of the body. This muscular action, together with the physical interaction between the body and...

Muscles, elastic energy, and the dynamics of body stiffness in swimming eels.
September 1, 1998... INTRODUCTION In vertebrates, studies of locomotor dynamics have broadened our view of muscle function beyond the classical model of forceful shortening. For example, measurements of muscle activity patterns (electromyography, "EMG") in...

Picture Control: The Electron Microscope and te Transformation of Biology in America, 1940-1960.
September 1, 1998... Picture Control: The Electron Microscope and the Transformation of Biology in America, 1940-1960. Nicolas Rasmussen. Stanford University Press, 1997, xii + 338 pages, illustrations, index; cloth $55.00 (ISBN 0-8047-2837-2). All too often...

Functional Morphology in Vertebrate Paleontology.
September 1, 1998... Functional Morphology in Vertebrate Paleontology. J. J. Thomason, ed. Cambridge University Press, Cambridge, 1997. xi + 277; paperback (ISBN 0-521-62921-7). The frustrating thing about extinct animals is that they are dead. We can study...

Biology by Numbers: An Encouragement to Quantitative Thinking.
September 1, 1998... Biology by Numbers: An Encouragement to Quantitative Thinking. Richard F. Burton. Cambridge University Press, 1998. xvi, 238 pages; hardback $59.95 (ISBN 0-521-57156-1); paperback $19.95 (ISBN 0-521-57698-9). From title onward, Burton...

Osteology of the Reptiles.
September 1, 1998... Osteology of the Reptiles. Alfre Sherwood Romer. Krieger Publishing Company, Malabar, Florida, 1997. xxvii + 772 pages $96.50 (ISBN 0-89464-985-x). This major work, originally published in 1956 by the University of Chicago Press, has become...

Selection in Natural Populations.
September 1, 1998... Selection in Natural Populations. Jeffry B. Mitton. Oxford University Press, 1998.240 pages; $60.00, (ISBN 0-19-506352-x). The title of this readable little book about evolution is really a subtitle. The title should be something like Enzyme...

The Rise of Birds: 225 Million Years of Evolution.
September 1, 1998... The Rise of Birds: 225 Million Years of Evolution. Sankar Chatterje. The Johns Hopkins University Press, Baltimore, 1997. xvi + 312 pp. Hardcover $39.95. (ISBN 0-8018-5615-9) Few fields in vertebrate paleontology have gathered as much recent...