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Integrating detailed studies of ecology and evolution with modern techniques of developmental genetics and molecular biology has the potential to be one of the most informative approaches to understanding the origins of biological diversity and morphological disparity. Anolis lizards are well-studied and will serve as an ideal model system for integrating these disparate fields. Anoles have undergone a remarkable pattern of convergent evolution across the Greater Antilles in which similar sets of habitat specialists have evolved repeatedly on different islands (Losos et al. 1998). Within an island, species have diverged in both morphology and behavior to adapt to different ecological niches. One aspect of divergence is limb length: relatively long-limbed species tend to use broad surfaces such as tree trunks or the ground while short-limbed species tend to be found on narrower surfaces such as twigs. Functional studies indicate that these differences, along with differences in head and body dimensions, tail length, and number of toe lamellae are adaptive in that they provide different functional capabilities appropriate to the different habitats. Thus, Anolis has the potential to allow for one of the first comprehensive studies of how development changes across both ecological and evolutionary time scales. The goal of this study is to present a developmental staging series for A. sagrei that will serve as the standard by which future investigations of Anolis embryology and developmental genetics may be compared. We also discuss the issues of husbandry and care for this species that will need to be understood and standardized to make this species amenable to laboratory rearing and experimentation.

Sexual dimorphisms vary widely among species. This variation must arise through sex-specific evolutionary modifications to developmental processes. Anolis lizards vary extensively in their expression of cranial dimorphism. Compared with other Anolis species, members of the carolinensis clade have evolved relatively high levels of cranial dimorphism; males of this clade have exceptionally long faces relative to conspecific females. Developmentally, this facial length dimorphism arises through an evolutionarily novel, clade-specific strategy. Our analyses herein reveal that sex-specific regulation of the oestrogen pathway underlies evolution of this exaggerated male phenotype, rather than the androgen or insulin growth factor pathways that have long been considered the primary regulators of male-biased dimorphism among vertebrates. Our results suggest greater intricacy in the genetic mechanisms that underlie sexual dimorphisms than previously appreciated., Organismic and Evolutionary Biology

Background: The effectiveness of antipsychotic monotherapy in schizoaffective disorder is limited, and further constrained by safety concerns.Aims: We aimed to compare the efficacy, tolerability and safety profile of the new pharmaceutical, olanzapine, with haloperidol.Method: Data were assessed from 300 DSM-III-R schizoaffective subjects from a larger double-blind prospective international study. Subjects were randomly allocated to six weeks of olanzapine (5-20 mg) or haloperidol (5-20 mg) treatment; responders were followed for up to one year of double-blind, long-term maintenance therapy.Results: Olanzapine-treated patients achieved a statistically significant greater improvement than haloperidol treated patients on overall measures of efficacy, including clinical response. Significantly fewer olanzapine patients left the study early, and fewer adverse events were observed among those receiving olanzapine. During maintenance, olanzapine-treated patients continued to experience additional improvement, with fewer EPS but more weight gain than those on haloperidol.Conclusions: Olanzapine demonstrated substantial advantages over the conventional antipsychotic haloperidol in the management of schizoaffective disorder. [ABSTRACT FROM AUTHOR]

Objective: The primary intent of this study was to compare the efficacy and safety of olanzapine and placebo in the treatment of acute mania.Method: The design involved a random-assignment, double-blind, placebo-controlled parallel group study of 3 weeks' duration. After a 2- to 4-day screening period, qualified patients were assigned to either olanzapine (N = 70) or placebo (N = 69). Patients began double-blind therapy with either olanzapine, 10 mg, or placebo given once per day. After the first day of treatment, the daily dose could be adjusted upward or downward, as clinically indicated, by one capsule (olanzapine, 5 mg/day) within the allowed range of one to four capsules. The primary efficacy measure in the protocol was defined as a change from baseline to endpoint in total score on the Young Mania Rating Scale. Clinical response was defined a priori as a decrease of 50% or more from baseline in Young Mania Rating Scale total score.Results: The olanzapine group experienced significantly greater mean improvement in Young Mania Rating Scale total score than the placebo group. On the basis of the clinical response criteria, significantly more olanzapine-treated patients (48.6%) responded than those assigned to placebo (24.2%). Somnolence, dizziness, dry mouth, and weight gain occurred significantly more often with olanzapine. There were no statistically significant differences between the olanzapine-treated and placebo-treated patients with respect to measures of parkinsonism, akathisia, and dyskinesias. No discontinuations of treatment due to adverse events occurred in the olanzapine treatment group.Conclusions: The results from this study suggest that compared with placebo, olanzapine has superior efficacy for the symptoms of acute mania. [ABSTRACT FROM AUTHOR]