we investigate evolutionary changes when genome regions become completely sex-linked, by analyses of multiple species of flatworms (Platyhelminthes; among which schistosomes recently evolved gonochorism from ancestral hermaphroditism), and roundworms (Nematoda) ...
Further, the frequency distributions of sizes among fish lineages resemble those of most other animal taxa, in being right-skewed, even on a log scale. Using an approach that measures rates of size evolution (in darwins) within a formal phylogenetic framework, we interpret the shape of size ...
is one of the oldest, most widely farmed commercially important freshwater fish in the world. However, many undetermined phylogenetic relationships and origins of common carp lineages remain, which are obstacles to conservation and genetic breeding of this species. Phylogenetic analyses based on ...
thus, could be expected to be governed by highly conserved mechanisms throughout metazoan evolution. While the bottom ends of sex determination pathways indeed tend to be conserved1, the higher steps show extensive evolutionary flexibility, as they can be triggered...
百度试题 题目Fish __ from prehistoric sea creature. A.evolvedB.evolutionC.involved相关知识点: 试题来源: 解析 A 反馈 收藏
. Alternative models account for the possibility that all cases of sex change require stimulation from smaller conspecifics (universal induction-inhibition model) or that all fish have the genetic capacity to switch mechanisms, depending on changing ecological conditions and resulting changes in mating ...
BEIJING, March 24 (Xinhua) -- Fish fossils, dating back about 425 million years ago, are providing insights into the evolution of scales on bony fishes. Diversified scales are one of the most obvious exterior characteristics of fish and they can be distributed in different areas of a fish in...
Males of many species use multiple sexual ornaments in their courtship display. We investigate the evolution of female sexual preferences for more than a single male trait by the handicap process. The handicap process assumes that ornaments are indicators of male quality, and a female benefits from...
Immune system - Evolution, Defense, Adaptation: Virtually all organisms have at least one form of defense that helps repel disease-causing organisms. Advanced vertebrate animals, a group that includes humans, defend themselves against such microorganisms
The emergence of fish from the sea was one of the key moments that transformed the evolution of life on Earth. 海洋鱼类在陆上出现是地球生物进化史上的重要时刻之一。 www.joyen.net 2. Some scientists suggested that there had been a gradual evolution of life on earth. 一些科学家认为,地球上的...