1978 — 1980 |
Grant, Peter |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Ecology and Behavior of Darwin's Finches On Galapagos Islands @ University of Michigan Ann Arbor |
0.951 |
1980 — 1983 |
Grant, Peter |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Ecology and Behavior of Geospiza On the Galapagos Islands @ University of Michigan Ann Arbor |
0.951 |
1986 — 1992 |
Grant, Peter [⬀] |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Ecology and Behavior of Darwin's Finches On the Galapagos Islands |
0.951 |
1988 — 1990 |
Grant, Peter [⬀] Lyon, Bruce |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Dissertation Research: Costs and Benefits of Intraspecific Brood Parasitism
Providing parental care to offspring is the usual mode ofnurturing in birds. However, in a variety of species, some females lay eggs in the nests of other individuals of their own species, which then rear the offspring. There is increasing evidence that this intraspecific brood parasitism is a widespread phenomenon in birds. However, the adaptive significance of this behavior remains unclear. For almost all of the seventy odd species where intraspecific brood parasitism been documented, the identity of the parasitic females, or what they gain by laying eggs in the nests of other females, is unknown. The widespread occurrence of intraspecific brood parasitism raises some fundamental questions about the costs and benefits of providing parental care to offspring in particular, and about the optimization of life history strategies in general. Tounderstand the ecological and evolutionary significance ofintraspecific brood parasitism in birds, a population of American coots in central British Columbia will be studied. Brood parasitism is common in this population and nearly a quarter of all nests were parasitized in 1987. Research to date has revealed that most parasitic females are territorial birds with nests of their own. Thus, parasitic females can be trapped at their own nests, individually marked, and their laying histories can be followed across years. The costs and benefits of brood parasitism to these parasitic females, and the behavioral, demographic and ecological factors associated with the behavior will be examined. Detailed studies like this are necessary if the broad patterns of intraspecific parasitism are to be understood.
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0.951 |
1992 — 1997 |
Grant, Peter [⬀] Grant, B. Rosemary |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Hybridization of Darwin's Finches On the Galapagos Islands
The study of hybridization is important in evolutionary biology because it reveals the forces at work in the final stages of speciation. Some populations of animal species commonly hybridize, but it is usually difficult if not impossible to determine the causes hybridization in nature. The proposed research takes advantage of an exceptionally favorable situation for investigating the causes of hybridization and the reasons for relatively high fitness of the hybrids. On the small island of Daphne Major in the Galapagos archipelago the medium ground finch, Geospza fortis, occasionally interbreeds with two others; G. scandens, a resident species, and G. fuliginosa, an immigrant. Pedigree analysis has shown that hybrids may survive and breed as well or better than the parental species, over several years. Ecological reasons for their fitness will be investigated by intensive study of feeding efficiencies and diets. Possible advantages arising from enhanced heterozygosity will be assessed by an analysis of inbreeding effects in the G. fortis and G. scandens populations. Causes of interbreeding will be identified by statistical analysis of mating patterns. Results will be of theoretical importance to our understanding of speciation and the role of hybridization in maintaining genetic variation in small and potentially endangered populations.
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0.951 |
1998 — 1999 |
Grant, Peter [⬀] Grant, B. Rosemary |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Sger: Effects of El Nino On Darwin's Finches
Grant 9806449 This award will be used to mobilize a quick response to the El Nino event that has developed in the central Pacific this winter. Dr. Grant and his students have been studying the birds of the Galapagos Islands for more than 20 years. It is expected that this El Nino event, predicted to be one of the largest on record, will result in a dramatically prolonged breeding season for Galapagos finches on the Galapagos Islands. This extended period of favorable conditions may have dramatic effects on the population size and demography of the study populations. Dr. Grant will test hypotheses concerning a) the heritability of life history traits, b) variation in age-specific fitness of hybrid birds, c) the fitness of inbred birds, d) the genetic structure of the two rarest populations which have recently experienced demographic and possibly genetic bottlenecks, and e) paternity of young birds estimated by observations of adults at nests. This study may provide novel insights to the mechanisms associated with evolutionary response to rapidly changing environmental conditions.
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0.951 |
2003 — 2007 |
Grant, Peter [⬀] Grant, B. Rosemary |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Speciation in Darwin's Finches
Speciation is the fundamental process in evolution that generates biological diversity. There is much debate on how it occurs and what the responsible mechanisms are. Most recent advances in understanding have come from genetic analyses of closely related species in the laboratory. Less is known from studies in nature about the ecological circumstances and microevolutionary forces responsible for speciation. The proposed research takes advantage of an exceptionally favorable situation provided by Darwin's Finches on the Galapagos islands. They are an intact group living in a largely undisturbed environment. Four species have been intensively studied on the small island of Daphne Major for 30 years. Building on this, populations at different stages in the speciation process will be investigated by a combination of methods; direct observations of individually marked birds to determine breeding patterns and survival, and responses to experimental playback of tape-recorded songs to determine behavioral limits to species recognition.
Results of this research will help to clarify the mechanisms of speciation under natural circumstances. There are two broader impacts. First, the research will elucidate factors that influence and maintain genetic variation in small and potentially endangered populations in need of conservation. Second, results of the long-term study will serve an educational function in the media.
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0.951 |
2007 — 2010 |
Grant, Peter (co-PI) [⬀] Stern, David [⬀] |
N/AActivity Code Description: No activity code was retrieved: click on the grant title for more information |
Dissertation Research: Evolution Through the Eyes of a Fly: the Genetic Basis of Interspecific Variation in Eye Size and Shape Between Two Closely Related Species of Drosophila
Plant and animal species exhibit an incredible diversity of form. Much of this morphological diversity is generated by genetic variation; however, the specific genetic modifications required to produce morphological variation are unknown in most cases. A comprehensive understanding of how diversity is produced requires determination of how differences in gene sequence alter trait form and function, as well as how natural selection acts upon the resulting variation. The fruit flies Drosophila mauritiana and Drosophila simulans have eyes that differ dramatically in size and shape. Through a combination of laboratory and field studies of these closely related species, the researchers propose (1) to identify genetic changes responsible for interspecific variation in eye size and shape, (2) to characterize the functional importance of variation in eye size and shape, and (3) to study the selective forces acting upon eye size and shape.
This study will improve understanding of how complex morphological traits evolve and why such traits differ between species. In addition, recent findings suggest that broad generalizations can be made from conclusions drawn from studies on model organisms such as Drosophila. Thus, findings from this study have the potential to be relevant for understanding the evolution of complex traits in other animal species and humans. This project will also allow the establishment of collaborations with two research labs in the UK; this association will allow the development of new research techniques such as the adaptation of software for analysis of complex traits in animals. Finally, an undergraduate student will be trained in research development and lab techniques and will have the opportunity to conduct independent research.
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0.951 |