Search results for "Inbreeding"
showing 7 items of 137 documents
Prolonged stigma and flower lifespan in females of the gynodioecious plant Geranium sylvaticum
2017
In gynodioecious plants females need a reproductive advantage over hermaphrodites to be maintained in the same population. Generally, three main proximate causes for a female advantage are considered: inbreeding avoidance, different resource allocation patterns, and differences in ecological interactions. A mechanism potentially causing a female advantage that is rarely discussed is a difference in floral longevity between the genders. Females may have a longer stigma lifespan than hermaphrodites, which can affect pollination. Stigma and flower lifespan are rarely documented in gynodioecious species, although it is a common observation in dioecious species that female plants flower longer t…
The effect of inbreeding rate on fitness, inbreeding depression and heterosis over a range of inbreeding coefficients
2014
Understanding the effects of inbreeding and genetic drift within populations and hybridization between genetically differentiated populations is important for many basic and applied questions in ecology and evolutionary biology. The magnitudes and even the directions of these effects can be influenced by various factors, especially by the current and historical population size (i.e. inbreeding rate). Using Drosophila littoralis as a model species, we studied the effect of inbreeding rate over a range of inbreeding levels on (i) mean fitness of a population (relative to that of an outbred control population), (ii) within‐population inbreeding depression (reduction in fitness of offspring fro…
¿Me voy o me quedo? Factores que influyen en la decisión de abandonar el lugar de nacimiento.
2014
Múltiples factores influyen en la decisión de dispersarse y en cuándo iniciar la dispersión, y su estudio proporciona evidencias de las causas y los determinantes de la dispersión. Los animales abandonan el lugar de nacimiento para dar solución a tres problemas fundamentales: pérdida de calidad del hábitat, competencia por los recursos, y riesgo de consanguinidad. La dispersión, sin embargo, no se lleva a cabo hasta que los individuos alcanzan una condición física adecuada, que permita alcanzar con éxito un nuevo lugar de asentamiento.
Genetics of condition and sexual selection
2007
FM Tarmo Ketolan ekologian ja ympäristönhoidon väitöskirjan ”Genetics of Condition and Sexual Selection” (Kunnon ja seksuaalivalinnan genetiikka) tarkastustilaisuus Jyväskylän yliopistossa. Vastaväittäjänä professori Juha Merilä (Helsingin yliopisto) ja kustoksena dosentti Janne Kotiaho.Linkki väitöksen pdf-versioon tiedotteen lopussa.FM Tarmo Ketola havaitsi väitöstutkimuksessaan, että geneettisesti huonolaatuiset sirkkayksilöt pystyvät käyttämään vähemmän energiaa aktiviteetteihin kuin hyvälaatuiset. Koska sisäsiitos lisäsi perusenergiankulutusta eli ruumiintoimintojen ylläpitoon kulutettua energiaa, se heikensi yksilöiden kuntoa.– Aiemmin on oletettu, että huonolaatuisilla yksilöillä on …
Relationship between inbreeding and milk production traits in two Italian dairy sheep breeds.
2022
The effects of inbreeding in livestock species breeds have been well documented and they have a negative impact on profitability. The objective of this study was to evaluate the levels of inbreeding in Sarda (SAR, n = 785) and Valle del Belice (VdB, n = 473) dairy sheep breeds and their impact on milk production traits. Two inbreeding coefficients (F) were estimated: using pedigree (FPED), or runs of homozygosity (ROH; FROH) at different minimum ROH lengths and different ROH classes. After the quality control, 38,779 single nucleotide polymorphisms remained for further analyses. A mixed-linear model was used to evaluate the impact of inbreeding coefficients on production traits within each …