Difference between revisions of "Kat Shaw"

From EEBedia
Jump to: navigation, search
(=Previous Research)
Line 40: Line 40:
 
What is especially interesting about these fish is that they have a very active social life.  Male threespines build nests on the substrate and exhibit a nuptial coloration to attract females and signal territoriality to other males.  When males spot a gravid female, they often perform a courtship dance and if the female is interested, she will enter the nest and leave a clutch of eggs for the male to fertilize.  The male may do this dance until he collects clutches from several females.  He then provides all parental care for the eggs, fanning oxygen over the eggs with his fins as they develop.  Males in some populations are very territorial and actively defend their nests and fry from intruders.
 
What is especially interesting about these fish is that they have a very active social life.  Male threespines build nests on the substrate and exhibit a nuptial coloration to attract females and signal territoriality to other males.  When males spot a gravid female, they often perform a courtship dance and if the female is interested, she will enter the nest and leave a clutch of eggs for the male to fertilize.  The male may do this dance until he collects clutches from several females.  He then provides all parental care for the eggs, fanning oxygen over the eggs with his fins as they develop.  Males in some populations are very territorial and actively defend their nests and fry from intruders.
  
==Previous Research==
+
===Previous Research===
 
Conspicuousness of courtship depends on potential threats to the nest in some population.  If large foraging groups of stickleback are present in a population they may cannibalize young in nests that they encounter.  Males in cannibalistic populations often utilize a less conspicuous courtship display and perform behaviors (diversionary displays) to distract groups away from a territory containing a nest and young.  Comparisons of courtship intensity in populations with varying levels of cannibalism have shown that some populations are more plastic in their behavioral response than others.  Males from populations in which some degree of cannibalism is present show an increase in courtship intensity when observed under laboratory conditions (where the threat of cannibalism is absent) as compared to observations under field conditions (where individuals experience foraging groups).  This reaction norm is related to population type in that the population experiencing the greatest frequency of foraging groups show the smallest increase in conspicuous courtship under laboratory conditions.  Males from a population in which no large foraging groups form show consistently high courtship intensity under both field and lab conditions.  Preliminary results involving lab-reared individuals from the low cannibalism and high cannibalism populations mirror the results of wild-caught fish suggesting an underlying genetic component to the difference in courtship intensity (see Shaw et al. 2007).  Further studies on the effects of cannibalism on behavior under laboratory conditions are being carried out by students at Clark University.  This will help determine the extent to which behavioral variation is exhibited upon exposure to foraging groups under standardized conditions.
 
Conspicuousness of courtship depends on potential threats to the nest in some population.  If large foraging groups of stickleback are present in a population they may cannibalize young in nests that they encounter.  Males in cannibalistic populations often utilize a less conspicuous courtship display and perform behaviors (diversionary displays) to distract groups away from a territory containing a nest and young.  Comparisons of courtship intensity in populations with varying levels of cannibalism have shown that some populations are more plastic in their behavioral response than others.  Males from populations in which some degree of cannibalism is present show an increase in courtship intensity when observed under laboratory conditions (where the threat of cannibalism is absent) as compared to observations under field conditions (where individuals experience foraging groups).  This reaction norm is related to population type in that the population experiencing the greatest frequency of foraging groups show the smallest increase in conspicuous courtship under laboratory conditions.  Males from a population in which no large foraging groups form show consistently high courtship intensity under both field and lab conditions.  Preliminary results involving lab-reared individuals from the low cannibalism and high cannibalism populations mirror the results of wild-caught fish suggesting an underlying genetic component to the difference in courtship intensity (see Shaw et al. 2007).  Further studies on the effects of cannibalism on behavior under laboratory conditions are being carried out by students at Clark University.  This will help determine the extent to which behavioral variation is exhibited upon exposure to foraging groups under standardized conditions.
  
==Current Research==
+
===Current Research===
 
My current interests are focused on alternative male mating tactics -- behaviors males use to obtain matings instead of (or in addition to) nesting and courtship behavior.  Drab colored male threespines have been observed to sneak along the substrate, hiding behind objects and in vegetation, in an attempt to rush into nests of courting males in order to fertilize eggs that are not their own.  There are several factors proposed to elicit sneaking in individual males but of greater interest is the fact that there are some populations in the Pacific Northwest where sneaking occurs at high frequencies (Alaska) and other populations where sneaking has never been observed (British Columbia).  Freshwater populations in this region are all derived from marine ancestors so it is plausible that ancestral plasticity in this behavior has influenced geographic variation in the propensity to sneak.  There may be certain characteristics (genetic and/or environmental) specific to populations in which sneaking is absent.  My current work involves:  
 
My current interests are focused on alternative male mating tactics -- behaviors males use to obtain matings instead of (or in addition to) nesting and courtship behavior.  Drab colored male threespines have been observed to sneak along the substrate, hiding behind objects and in vegetation, in an attempt to rush into nests of courting males in order to fertilize eggs that are not their own.  There are several factors proposed to elicit sneaking in individual males but of greater interest is the fact that there are some populations in the Pacific Northwest where sneaking occurs at high frequencies (Alaska) and other populations where sneaking has never been observed (British Columbia).  Freshwater populations in this region are all derived from marine ancestors so it is plausible that ancestral plasticity in this behavior has influenced geographic variation in the propensity to sneak.  There may be certain characteristics (genetic and/or environmental) specific to populations in which sneaking is absent.  My current work involves:  
  

Revision as of 19:08, 1 February 2008

Katherine Shaw, Doctoral Student

B.A./M.A. (2005) Clark University, Department of Biology

Doctoral Student (2005 - Present) University of Connecticut, Ecology & Evolutionary Biology


Contact Info:

Department of Ecology and Evolutionary Biology

75 North Eagleville Rd, U-43

Storrs, CT 06269

_______________________________________________

Office: TLS 363

Voice: (860) 486-4638

Fax: (860) 486-6364

Email: katherine.shaw@uconn.edu

Advisor: Carl Schlichting

Interests:

Behavioral ecology, phenotypic plasticity, ancestral behavioral plasticity, alternative reproductive tactics, fish biology, Gasterosteid behavior


Research:

Study Species

There are a number of stickleback species (Family: Gasterosteidae), many named for their number of dorsal spines (threespine, fourspine, ninespine, fifteenspine!). I've spent the last few years working with threespine stickleback (Gasterosteus aculeatus L) in British Columbia and Alaska, specifically studying population differences in reproductive behavior. Marine populations of threespines invaded freshwater environments during the last glacial recession between 15,000 and 10,000 years ago. Depending on the type of aquatic habitat invaded, populations have come to differ in morphology and behavior. This is especially interesting because, not only does it tell us much about how environment affects morphology and behavior but, since the ancestral (marine) populations have changed little in the last 20,000 years, we can determine the directionality of behavior and morphological changes in the more derived, freshwater populations.

What is especially interesting about these fish is that they have a very active social life. Male threespines build nests on the substrate and exhibit a nuptial coloration to attract females and signal territoriality to other males. When males spot a gravid female, they often perform a courtship dance and if the female is interested, she will enter the nest and leave a clutch of eggs for the male to fertilize. The male may do this dance until he collects clutches from several females. He then provides all parental care for the eggs, fanning oxygen over the eggs with his fins as they develop. Males in some populations are very territorial and actively defend their nests and fry from intruders.

Previous Research

Conspicuousness of courtship depends on potential threats to the nest in some population. If large foraging groups of stickleback are present in a population they may cannibalize young in nests that they encounter. Males in cannibalistic populations often utilize a less conspicuous courtship display and perform behaviors (diversionary displays) to distract groups away from a territory containing a nest and young. Comparisons of courtship intensity in populations with varying levels of cannibalism have shown that some populations are more plastic in their behavioral response than others. Males from populations in which some degree of cannibalism is present show an increase in courtship intensity when observed under laboratory conditions (where the threat of cannibalism is absent) as compared to observations under field conditions (where individuals experience foraging groups). This reaction norm is related to population type in that the population experiencing the greatest frequency of foraging groups show the smallest increase in conspicuous courtship under laboratory conditions. Males from a population in which no large foraging groups form show consistently high courtship intensity under both field and lab conditions. Preliminary results involving lab-reared individuals from the low cannibalism and high cannibalism populations mirror the results of wild-caught fish suggesting an underlying genetic component to the difference in courtship intensity (see Shaw et al. 2007). Further studies on the effects of cannibalism on behavior under laboratory conditions are being carried out by students at Clark University. This will help determine the extent to which behavioral variation is exhibited upon exposure to foraging groups under standardized conditions.

Current Research

My current interests are focused on alternative male mating tactics -- behaviors males use to obtain matings instead of (or in addition to) nesting and courtship behavior. Drab colored male threespines have been observed to sneak along the substrate, hiding behind objects and in vegetation, in an attempt to rush into nests of courting males in order to fertilize eggs that are not their own. There are several factors proposed to elicit sneaking in individual males but of greater interest is the fact that there are some populations in the Pacific Northwest where sneaking occurs at high frequencies (Alaska) and other populations where sneaking has never been observed (British Columbia). Freshwater populations in this region are all derived from marine ancestors so it is plausible that ancestral plasticity in this behavior has influenced geographic variation in the propensity to sneak. There may be certain characteristics (genetic and/or environmental) specific to populations in which sneaking is absent. My current work involves:

  1. Regional investigations of the conditional factors suggested to covary with sneaking behavior (sex ratio; inter-nest distances, visibility, etc.) Are any of these factors correlated with an in situ propensity to sneak both within and between regions (Alaska vs British Columbia)?
  1. Intra- and Interspecific comparisons of sneaker color variation and investigation of the adaptive significance of sneaking patterning. Is there low variability in sneaker coloration across populations? Are sneaking males utilizing crypsis or female mimicry?
  1. Laboratory-based comparisons of sneaking propensity with lab-reared individuals from sneaking and non-sneaking populations. Is there a genetic component underlying variation in sneaking propensity?

Publications:

Foster, S.A., K.A. Shaw, K.L. Robert, J. A. Baker. 2008. Benthic, limnetic and oceanic threespine stickleback: Profiles of reproductive behavior. Behaviour, in press.

Shaw, K.A., M.L. Scotti, S.A. Foster. 2007. Ancestral plasticity and the evolutionary diversification of courtship behaviour in threespine sticklebacks. Animal Behaviour 73: 415 – 422.