It is often proposed that the shape of animals evolves as a correlated response to selection on life history traits such as whole body growth and differentiation rates. This scenario is certainly true for shape variation that is an allometric consequence of body size variation, because body size is determined by growth and differentiation rates. However, we are aware of few examples in which development rate variation is correlated with body size-independent shape variation. In this study on the green treefrog, Hyla cinerea, we test whether that fraction of the variance in tibiofibula length and head width that is left after removing snout vent length as a covariate is correlated with either genetically or environmentally based variation in development rates. / Size-adjusted tibiofibula length and head width at metamorphosis are both positively genetically correlated with larval period length. Thus, relative limb and head proportions in adult treefrogs could evolve as a correlated response to selection on a larval life history trait. Neither larval growth rate nor juvenile growth rate is significantly genetically correlated with the morphological traits. The two size-adjusted morphological traits are strongly genetically correlated with each other, a situation which could either hinder or accelerate their joint evolution, depending on the directions of selection. / The growth rate of larvae raised under different food levels and temperatures had no effect on their size-adjusted head width or tibiofibula length at metamorphosis. The food-controlled rate at which small juveniles became large ones also had no influence on their shape. However, the head width versus snout vent length relationship among metamorphs has a shallower slope than the same relationship within growing juveniles. Thus, size at metamorphosis alone controls head width at a given larger body size. To our knowledge, we are the first to identify this difference in allometries as a potential source of size-independent shape variation in adult frogs. / Source: Dissertation Abstracts International, Volume: 51-01, Section: B, page: 0106. / Major Professor: Joseph Travis. / Thesis (Ph.D.)--The Florida State University, 1989.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_78154 |
| Contributors | Blouin, Michael Scott., Florida State University |
| Source Sets | Florida State University |
| Language | English |
| Detected Language | English |
| Type | Text |
| Format | 77 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
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