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Geology topics

J.S. Godley

Publications and source records attributed to J.S. Godley.

2 recordsLinked to original sources

Long generation time delays the genetic response to habitat fragmentation in the threatened florida sand skink

A recent study showed that populations of the threatened Florida Sand Skink had limited loss of genetic diversity over the past 60 yr as a consequence of anthropogenic fragmentation. This study assumed that 60 yr represents 3037 generations for the Florida Sand Skink, but a new evaluation of markrecapture data shows that 60 yr represents only about 15 generations. This result suggests that too little time may have passed to observe the full genetic consequences of contemporary anthropogenic fragmentation in the Florida Sand Skink and reinforces similar results from other species. We suggest that snapshots of existing genetic variability in fragmented populations are limited in their ability to predict the evolutionary fate of a species unless life-history attributes of the organism are taken into account. Copyright 2010 Society for the Study of Amphibians and Reptiles.

Conference Paper

Estimating prey size and number in crayfish-eating snakes, genus Regina

Snakes of the genus Regina feed almost exclusively on crayfish. The paired, symmetrical gastroliths of crayfish are not digested and are detectable from x-rays of the snake. Gastrolith length is directly proportional to carapace length and can be obtained from x-rays. Carapace length can be converted to kcal of ingested energy. Using these relationships and repeated captures of radio-telemetered Regina, estimates of food consumption and energy intake by freeliving snakes are feasible. New information on prey selectivity, feeding behavior, and predator-prey size relations in Regina grahami and R. septemvittata are presented and compared with similar data for other snakes.

Herpetologica