Essays about: "sexual dimorphism"

Showing result 6 - 10 of 11 essays containing the words sexual dimorphism.

1. 6. Sexual selection and extinction in deer

   University essay from Uppsala universitet/Institutionen för biologisk grundutbildning

   Author : Saloume Bazyan; [2013]
   Keywords : Sexual selection; Extinction; Cervidae; Size dimorphism; mating system;

   Abstract : By performing a comparative analysis and using phylogenetic relationships of the Cervidaefamily this study aimed to address whether or not sexual selection may play a role in the extinctionof species by making species more vulnerable to extinction. The role of sexual selection in makingspecies more vulnerable to extinction is largely unexplored, and several factors such as ecologicaland life history traits may increase the risk of extinction. READ MORE

3. 7. Effects of domestication on social support in chickens (Gallus gallus)

   University essay from Institutionen för fysik, kemi och biologi; Tekniska högskolan

   Author : Rebecca Katajamaa; [2012]
   Keywords : Social support; White Leghorn; red junglefowl; domestication; social behaviour;

   Abstract : Social support is thought to give animals benefits from social partners, such as improved coping with challenges. The aim of this study was to investigate differences in social support in the red junglefowl (RJF) and a domestic layer strain, the White Leghorn (WL). READ MORE

4. 8. Impact of a maternal high-fat diet on mouse placental epigenetic programming

   University essay from SLU/Dept. of Animal Breeding and Genetics

   Author : Bahriye Karakas; [2011]
   Keywords : epigenetic; high-fat diet; placenta; DOHaD; sexual dimorphism;

   Abstract : OBJECTIVE: To assess how nutrient intakes of mouse mothers during pregnancy influence placental and fetal growth, we fed pregnant mother with a high-fat diet (HFD) and collect fetus and placentas in the middle of fetal period and at term. MATERIAL and METHODS: We studied gene expression by RT-qPCR and DNA methylation by LUMA to understand the molecular mechanisms of placental epigenetic programming in the labyrinth layer of the placenta, where nutrient exchanges take place. READ MORE

5. 9. Which is the costlier sex? : Sexual dimorphism and resource allocation in a dioecious herb, Silene dioica

   University essay from Institutionen för ekologi, miljö och geovetenskap

   Author : Elisabet Åkerlund; [2011]
   Keywords : sexual dimorphism; resource allocation; cost of reproduction;

   Abstract : Life-history theory proposes that different activities, such as growth, maintenance and reproduction compete for limited resources and therefore, life-history traits are bound together by physiological trade-offs. In dioecious species, females are assumed to invest a higher amount of resources in reproduction in comparison with males and this higher investment in reproduction is then assumed to have numerous consequences for the expression of other life-history traits. READ MORE

6. 10. Diurnal rhythm of the savannah elephant (Loxodonta africana africana) in Maasai Mara National Reserve, Kenya

   University essay from SLU/Dept. of Animal Environment and Health

   Author : Mikaela Persson Wallenius; [2010]
   Keywords : Elephants; Loxodonta africana; diurnal rhythm; hindgut fermenters;

   Abstract : Elephants are hindgut fermenters, which affects their diurnal rhythm. To reach their nutrient demands, elephants must eat almost constantly throughout the light part of the day. Sexual dimorphism may also affect their behavioral patterns. READ MORE