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Phenotype Matching (phenotype + matching)
Selected AbstractsPhenotype matching and inbreeding avoidance in African elephantsMOLECULAR ECOLOGY, Issue 21 2007JIM MOORE Abstract Perhaps the most important ,decision' made by any animal (or plant) is whether to disperse , leave kith and kin, or remain with the familiar and related. The benefits of staying at home are obvious, so dispersal requires an explanation , and the most popular is that dispersal functions to avoid inbreeding depression. Strong support comes from the observation that dispersal is so often sex biased. Simply put, all else being equal members of both sexes should prefer to remain philopatric, but this would lead to inbreeding depression so members of one sex have to disperse. In principle, this link between inbreeding depression and sex-biased dispersal could be broken if individuals recognize close kin and avoid mating with them. Archie et al. (2007) provide one of the most compelling analyses to date of the interaction among inbreeding avoidance, kin recognition and mating strategies in any mammal, clearly showing that elephants recognize even close paternal kin and avoid mating with them. Their important results illuminate the subtleties of elephant inbreeding avoidance as well as illustrate the difficulty of arriving at definitive answers to questions about the evolution of dispersal behaviour. [source] Host specificity, phenotype matching and the evolution of reproductive isolation in a coevolved plant,pollinator mutualismMOLECULAR ECOLOGY, Issue 24 2009ANNA G. HIMLER Coevolutionary interactions between plants and their associated pollinators and seed dispersers are thought to have promoted the diversification of flowering plants (Raven 1977; Regal 1977; Stebbins 1981). The actual mechanisms by which pollinators could drive species diversification in plants are not fully understood. However, it is thought that pollinator host specialization can influence the evolution of reproductive isolation among plant populations because the pollinator's choice of host is what determines patterns of gene flow in its host plant, and host choice may also have important consequences on pollinator and host fitness (Grant 1949; Bawa 1992). In this issue of Molecular Ecology, Smith et al. (2009) present a very interesting study that addresses how host specialization affects pollinator fitness and patterns of gene flow in a plant host. Several aspects of this study match elements of a seminal mathematical model of plant,pollinator codivergence (Kiester et al. 1984) suggesting that reciprocal selection for matched plant and pollinator reproductive traits may lead to speciation in the host and its pollinator when there is strong host specialization and a pattern of geographic subdivision. Smith et al.'s study represents an important step to fill the gap in our understanding of how reciprocal selection may lead to speciation in coevolved plant,pollinator mutualisms. [source] Host specificity and reproductive success of yucca moths (Tegeticula spp.MOLECULAR ECOLOGY, Issue 24 2009Lepidoptera: Prodoxidae) mirror patterns of gene flow between host plant varieties of the Joshua tree (Yucca brevifolia: Agavaceae) Abstract Coevolution between flowering plants and their pollinators is thought to have generated much of the diversity of life on Earth, but the population processes that may have produced these macroevolutionary patterns remain unclear. Mathematical models of coevolution in obligate pollination mutualisms suggest that phenotype matching between plants and their pollinators can generate reproductive isolation. Here, we test this hypothesis using a natural experiment that examines the role of natural selection on phenotype matching between yuccas and yucca moths (Tegeticula spp.) in mediating reproductive isolation between two varieties of Joshua tree (Yucca brevifolia var. brevifolia and Y. brevifolia var. jaegeriana). Using passive monitoring techniques, DNA barcoding, microsatellite DNA genotyping, and sibship reconstruction, we track host specificity and the fitness consequences of host choice in a zone of sympatry. We show that the two moth species differ in their degree of host specificity and that oviposition on a foreign host plant results in the production of fewer offspring. This difference in host specificity between the two moth species mirrors patterns of chloroplast introgression from west to east between host varieties, suggesting that natural selection acting on pollinator phenotypes mediates gene flow and reproductive isolation between Joshua-tree varieties. [source] Aggressiveness is associated with genetic diversity in landlocked salmon (Salmo salar)MOLECULAR ECOLOGY, Issue 9 2003Katriina Tiira Abstract The amount of intraindividual genetic variation has often been found to have profound effects on life history traits. However, studies concerning the relationship between behaviour and genetic diversity are scarce. Aggressiveness is an important component of competitive ability in juvenile salmonids affecting their later performance and survival. In this study, we used an experimental approach to test the prediction that juveniles with low estimated genetic diversity should be less aggressive than juveniles with high estimated genetic diversity in fry from a highly endangered population of land-locked salmon (Salmo salar). This was achieved by using a method enabling the accurate estimation of offspring genetic diversity based on parental microsatellite genotype data. This allowed us to create two groups of offspring expected to have high or low genetic diversity in which aggressive behaviour could be compared. Salmon fry with low estimated genetic diversity were significantly less aggressive than fry with high estimated genetic diversity. Closer analysis of the data suggested that this difference was due to differences in more costly acts of aggression. Our result may reflect a direct effect of genetic variation on a fitness-related trait; however, we cannot rule out an alternative explanation of allele-specific phenotype matching, where lowered aggression is expressed towards genetically more similar individuals. [source] Inclusive fitness in human relationshipsBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2009J. PHILIPPE RUSHTON For Homo sapiens, inclusive fitness theory goes well beyond ,kin'. As William Hamilton hypothesized, genes can increase the probability of their own survival by bringing about the reproduction of not only family members with whom they share copies, but also of any individuals with whom they share copies. Research with Hamilton's theory on people is less well known and remains controversial. This review shows: (1) spouses and close friends assort on blood groups and that similarity predicts fertility; (2) twin and adoption studies find genes rather than upbringing cause people to positively assort; (3) phenotype matching is more pronounced on more heritable items within sets of homogeneous traits; (4) bereavement studies find grief is greater following the death of a more similar co-twin or child; (5) studies of face perception find people prefer and trust those who look like them; and (6) DNA variance within and between ethnic groups is equivalent to that within and between families. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 96, 8,12. [source] ,O sibling, where art thou?'- a review of avian sibling recognition with respect to the mammalian literatureBIOLOGICAL REVIEWS, Issue 1 2004Shinichi Nakagawa ABSTRACT Avian literature on sibling recognition is rare compared to that developed by mammalian researchers. We compare avian and mammalian research on sibling recognition to identify why avian work is rare, how approaches differ and what avian and mammalian researchers can learn from each other. Three factors: (1) biological differences between birds and mammals, (2) conceptual biases and (3) practical constraints, appear to influence our current understanding. Avian research focuses on colonial species because sibling recognition is considered adaptive where,mixing potential'of dependent young is high; research on a wide range of species, breeding systems and ecological conditions is now needed. Studies of acoustic recognition cues dominate avian literature; other types of cues (e.g. visual, olfactory) deserve further attention. The effect of gender on avian sibling recognition has yet to be investigated; mammalian work shows that gender can have important influences. Most importantly, many researchers assume that birds recognise siblings through,direct familiarisation'(commonly known as associative learning or familiarity); future experiments should also incorporate tests for,indirect familiarisation'(commonly known as phenotype matching). If direct familiarisation proves crucial, avian research should investigate how periods of separation influence sibling discrimination. Mammalian researchers typically interpret sibling recognition in broad functional terms (nepotism, optimal outbreeding); some avian researchers more successfully identify specific and testable adaptive explanations, with greater relevance to natural contexts. We end by reporting exciting discoveries from recent studies of avian sibling recognition that inspire further interest in this topic. [source] | ||||||||||