Published online by Cambridge University Press: 10 August 2009
CHAPTER SUMMARY
The wide range of variation in reproductive tactics displayed among teleost fishes has provided a rich source of natural experiments for investigating the neural mechanisms of alternative reproductive tactics (ARTs). These studies have mainly focused on identifying the location and extent of neuropeptide-containing cells in the forebrain's preoptic area (POA), in part, because of the well-established influence of these neurons on reproductive mechanisms. We first review the ARTs of teleost species that have served as model systems for investigating the neural mechanisms of reproductive plasticity and then the general organization of the POA of vertebrates. Comparative surveys then show how life-history trajectories and reproductive tactics vary with inter- and intrasexual dimorphisms in the size and number of POA neurons that synthesize either arginine vasotocin (AVT) or gonadotropin-releasing hormone (GnRH). The emerging evidence for the potential role of neurosteroids in mechanisms of reproductive plasticity inclusive of ARTs is then considered before concluding with a listing of a suite of neuroendocrinological traits that may provide proximate mechanisms essential to the widespread evolution of ARTs among teleost fish.
INTRODUCTION: DIVERGENT LIFE-HISTORY TRAJECTORIES
A major theme that continues to emerge from many studies of the neural mechanisms of ARTs is the uncoupling of gonadal and neurobiological traits that provides for the adaptable patterning of suites of mechanisms between alternative behavioral phenotypes (Bass 1992).
To save this book to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.