41. Then, it is possible to induce genetic females to differentiate as phenotypic males (termed “neomales”) by experimental implantation of androgenic glands during early sexual differentiation. These neomales are then crossed
The evolutionary advantage of different sexual systems in multicellular eukaryotes is still not well understood, because the differentiation into male and female individuals halves offspring production compared with asexuality. Here we propose that various physiological adaptations to oxidative stress could hav...
The Evolution of Diet The Evolution of Diet By Ann Gibbons Photographs by Matthieu Paley Some experts say modern humans should eat from a Stone Age menu. What's on it may surprise you. The Tsimane of Boliviaget most of their food from the river, the forest, or fields and gardens carved...
Interestingly, we found that throughout species evolution, the proportion of repetitive elements increased to approximately 50%, while the proportion of coding sequences (CDSs) decreased to approximately 5% (Fig. 6C, right panel). We discovered that more than half of the retrotransposons in humans...
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Sexual dimorphism of body size has been the subject of numerous studies, but few have examined sexual shape dimorphism (SShD) and its evolution. Allometry, the shape change associated with size variation, has been suggested to be a main component of SShD
We measured whether males of five species of poeciliid fish made detours to the right or left of a vertical-bar obstacle in order to approach a group of fe... A Bisazza,R Pignatti,G Vallortigara - 《Animal Behaviour》 被引量: 189发表: 1997年 Male competition, female mate choice and sex...
Understanding how and why menopause has evolved is a long-standing challenge across disciplines. Females can typically maximize their reproductive success by reproducing for the whole of their adult life. In humans, however, women cease reproduction seve
The classical theory treats life history evolution as an optimization problem: given particular ecological factors (e.g., predators, nutrition) that affect an organism's probability of survival and reproduction, and given limiting constraints and trade-offs intrinsic to the organism, what are the opt...
Before the novelty of this newly democratized world of content could sink in, the core problem shifted from making content available to finding the right content. Enter the rise of search engines. Now, I've got no problem with search—I use it as a regular part of doing business. For exa...