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 ….a better integration of neutral and adaptive genetic variation and their interplay
with species distribution and the environment.
 ….a better integration of neutral and adaptive genetic variation and their interplay
with species distribution and the environment.
 In this respect, key questions are: (i) how has recent global change (i.e., land use
and land cover as well as climate change) affected patterns of neutral and adaptive
genetic variation; and (ii) are species likely to adapt to ongoing global change on an
ecological time scale?
 Over the past ten years, landscape genetics has increased our understanding of two
main evolutionary processes: gene flow and adaptation.
 Consequently, it is time for landscape genetics to evolve from a descriptive to a
more predictive science to have more impact on conservation management.
 In an example from Ecuador, a tropical area recognized as a hotspot of biodiversity,
Thomassen et al. [26] combined species-distribution models, landscape genetics,
and reserve-design algorithms to prioritize seven amphibian, bird, and mammal
species. They concluded that priority areas for intraspecific variation, located
mainly on the slopes of the Andes, were largely congruent among species, but
clearly underrepresented in existing reserves
 …to go beyond the mere description of patterns.
(diploide, reproducción sexual etc.)
Una población grande para reproducción
Entrecruzamiento al azar
Ningún cambio alélico debido a las mutaciones
Ninguna inmigración y emigración
Ninguna selección natural
 Intra vs intersexual
 Acción sobre el fenotipo!
 Evolución se trata de cambios de frecuencias alélicos en poblaciones, selección
natural del selección de individuos.
 Efecto fundador
 Cuello de botella
 Seleccion intrasexual (male-male competition)
 Selección intersexual (female choice)
 Superioridad de heterocigoto
 Selección natural disruptiva
 Selección natural direccional
 Selección natural normalizadora
 Five families are described in which autopsy-confirmed presenile Alzheimer's disease
(AD) has occurred in men and women over multiple generations consistent with
autosomal dominant inheritance. All 5 families are descendants of a group of
immigrants known as the Volga Germans who came to the United States between
1870 and 1920. Their ancestors moved from Germany to the southern Volga region of
Russia in the 1760s. All 5 American families are descendants of persons originally
living in two small adjacent Volga German villages and share several surnames
known to have been present in the census records of those villages. Although a
single affected common ancestor cannot be identified, it is likely that the AD in
these families represents an autosomal dominant gene inherited from one ancestor.
This information is of importance in the genetic study of AD in these families
because it greatly increases the probability of genetic homogeneity. There are more
than 300,000 American descendants of the Volga Germans, and the prevalence of AD
has never been studies in this population.
 Male secondary sexual ornaments are widespread among polygynous animals1 where
they apparently arise through __________ and differential mating success of males2–
5. Darwin1 and Fisher2 suggested that _______should also select for extravagant male
ornaments in monogamous birds because female preference for ornamented males
should result in earlier breeding which would increase male reproductive success by
enhancing the quality and/or the quantity of offspring raised each year. In such cases
female reproductive success should be positively related to body condition6 and a
heritable component of the time of breeding should be affected by stabilizing
selection7. Female preferences for ornamented males would be favoured by sexual
selection because such choosy females would have a greater probability of bearing
ornamented sons with an increased chance of pairing up early. I report here that in
the monogamous swallow, Hirundo rustica, males with experimentally elongated tail
ornaments obtain mates more quickly than males with shorter tails, and enjoy
increased reproductive output in one breeding season. Such males are also preferred
by females seeking extra-pair-bond copulations. Thus male sexual ornaments may
also be maintained by female mate choice in monogamous species.
 East African cichlid fishes represent one of the most striking examples of rapid and
convergent evolutionary radiation among vertebrates. Models of ecological speciation
would suggest that functional divergence in feeding morphology has contributed to the
origin and maintenance of cichlid species diversity. However, definitive evidence for the
action of natural selection has been missing. Here we use quantitative genetics to
identify regions of the cichlid genome responsible for functionally important shape
differences in the oral jaw apparatus. The consistent direction of effects for individual
quantitative trait loci suggest that cichlid jaws and teeth evolved in response to strong
selection. Moreover, several chromosomal regions contain a disproportionate number of
quantitative trait loci, indicating a prominent role for pleiotropy or genetic linkage in
the divergence of this character complex. Of particular interest are genomic intervals
with concerted effects on both the length and height of the lower jaw. Coordinated
changes in this area of the oral jaw apparatus are predicted to have direct consequences
for the speed and strength of jaw movement. Taken together, our results imply that the
rapid and replicative nature of cichlid trophic evolution is the result of _____________
on chromosomal packages that encode functionally linked aspects of the craniofacial
skeleton.
 Two recent studies have shown a relationship between male height and number of
offspring in contemporary developed-world populations. One of them argues as a
result that directional selection for male tallness is both positive and unconstrained.
This paper uses data from a large and socially representative national cohort of men
who were born in Britain in March 1958. Taller men were less likely to be childless
than shorter ones. They did not have a greater mean number of children. If
anything, the pattern was the reverse, since men from higher socioeconomic groups
tended to be taller and also to have smaller families. However, clear evidence was
found that men who were taller than average were more likely to find a long-term
partner, and also more likely to have several different long-term partners. This
confirms the finding that tall men are considered more attractive and suggests that,
in a noncontracepting environment, they would have more children. There is also
evidence of _____________, since extremely tall men had an excess of health
problems and an increased likelihood of childlessness. The conclusion is that male
tallness has been selected for in recent human evolution but has been constrained
by developmental factors and stabilizing selection on the extremely tall.
 Leer Capitulo 19!!!
 Coevolucion
 Aptacion, adaptación, exaptacion
 Mimetismo
 Ecotipos y clinas