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Research has been conducted on the convergent evolution among aquatic Anolis lizards. The hypothesis that these lizards are convergent in morphology has been examined and the results are reported.

We document the decimation and recovery of the commonest lizard species, Anolis sagrei, on 66 islands in the Bahamas that were directly hit by Hurricane Floyd in September 1999. Before the hurricane, an island's area was a better predictor of the occurrence of A. sagrei than was its altitude. Immediately after, altitude was a better predictor: Apparently all lizards on islands lower than about 3 meters maximum elevation perished in the storm surge. After about 1 year, area again became the better predictor. By 19 months after the hurricane, A. sagrei populations occurred on 88% of the islands they formerly occupied. Recovery occurred via overwater colonization and propagation from eggs that survived inundation, mechanisms that were enhanced by larger island area. Thus, natural processes first destroyed and then quickly restored a highly regular species-area distribution., The community species-area relation, describing the increase of species number with increasing area, is one of ecology's most pervasive regularities--even, perhaps, one of its few 'laws' (1-6). This curve is [...]

Author(s): Thomas W. Schoener (corresponding author) [1]; David A. Spiller [1]; Jonathan B. Losos [2] There has been considerable research on both top-down effects [1, 2] and on disturbances [3, [...]

Author(s): Jonathan B. Losos [1]; Dolph Schluter [2] Large islands typically have more species than comparable smaller islands. Ecological theories, the most influential being the equilibrium theory of island biogeography [...]

The relationship between sexual size dimorphism (SSD) and habitat use has been studied in Greater Antillean Anolis lizards. Findings show the major ecomorph classes differ in SSD degree. The habitat-specific sexual dimorphism seen suggests that adaptation of Anolis species to their environments is more complex than had been thought.

It cannot be argued that there is no need to use phylogenetic information. However, phylogenetic information should be considered at an earlier stage of analysis. If there is no connection between phylogenetic and phenotypic similarity, then subsequent use of phylogenetic approaches may not be justified. If such a connection does exist, then phylogenetic information should be integrated into statistical analysis and evolutionary interpretation. It is important to consider whether there are circumstances in which phylogenetic approaches should not be used at all.

Research demonstrates the key role of the environment in biological morphology, using lizard genera Anolis and Sceloporus as examples. Topics include a comparison of morphological traits, such as limb proportions and tail length, and of geographic location, such as tropic and arid, for both species.

The ability of organisms to perform specific ecological 'tasks,' such as capturing prey or escaping predators, may have far-reaching effects on organismal survival, reproduction, and growth (e.g., Arnold 1983; Pough [...]

In the past decade, a number of ancestral character state reconstruction methods have been developed for testing evolutionary hypotheses (Huey and Bennett 1987; Swofford and Maddison 1987; Maddison 1991; Martins [...]

The view that environment has a key impact on the evolution of morphology has been supported by research using populations of the lizard Anolis sagrei. These were introduced onto small islands in the Bahamas from a nearby source. It was found that they quickly differentiated from each other over a period of between 10 and 14 years. It can be ascertained that populations respond quickly to new environmental circumstances. Furthermore, this response has similarities with large-scale patterns seen on macroevolutionary timescales.

Decreasing the perch diameter in lab conditions leads to a decrease in sprint speed but has an insignificant effect on the jumping ability of Anolis lizards. The effect of perch diameter on the escape behavior of lizards can be predicted by diameter effect on locomotor capacities of lizards. The jumping ability of lizards depends upon the location, to maximize their locomotor abilities.

Biologists have long debated whether evolution is inherently directional. The modern synthesis of the 1940s rid evolutionary biology of teleological theories such as aristogenesis and orthogenesis (Romer 1949; Mayr 1988), [...]

A study of aggressive visual responses of male Anolis lizards revealed that the males discriminated between heterospecific video sequences and conspecific ones, with the stimuli being matched for overall display. The display pattern and/or morphological cues mediated species recognition. Synchronous displays served as a signal of threat to introducing conspecifics.

I tested biomechanical predictions that morphological proportions (snout-vent length, forelimb length, hindlimb length, tail length, and mass) and maximal springting and jumping ability have evolved concordantly among 15 species of Anolis lizards from Jamaica and Puerto Rico. Based on a phylogenetic hypothesis for these species, the ancestor reconstruction and contrast approaches were useed to test hypotheses that variables coevolved. Evolutionary change in all morphological and performance variables scales positively with evolution of body size (represented by snout-vent length); size evolution accounts for greater than 50% of the variance in sprinting and jumping evolution. With the effect of the evolution of body size removed, increases in hindlimb length are associated with increases in sprinting and jumping capability. When further variables are removed, evolution in forelimb and tail length exhibits a negative relationship with evolution of both performance measures. The success of the biomechanical predictions indicates that the assumption that evolution in other variables (e.g., muscle mass and composition) did not affect performance evolution is probably correct; evolution of the morphological variables accounts for approximately 80% of the evolutionary change in performance ability. In this case, however, such assumptions are clade-specific; extrapolation to taxa outside the clade is thus unwarranted. The results have implications concerning ecomorphological evolution. The observed relationship between forelimb and tail length and ecology probably is a spurious result of the correlation between these variables and hindlimb length. Further, because the evolution of jumping and sprinting ability are closely linked, the ability to adapt to certain microhabitats may be limited.