|
|
此文章由 pirate258 原创或转贴，不代表本站立场和观点，版权归 oursteps.com.au 和作者 pirate258 所有！转贴必须注明作者、出处和本声明，并保持内容完整
All western blue groper begin life as females and some, but
not all, change sex to males later in life. Biologists call this
type of change ‘protogynous hermaphroditism’, which is
very common for members of the wrasse family.
On average, female western blue groper take 15 to 20
years to reach sexual maturity, when they are around
650 mm in length.
Sex change in western blue groper occurs at a length of
about 820 mm and at an age of between 30 and 35 years.
This change in sex is closely associated with a change in
the groper’s colour from green to blue.
Western blue groper prefer to live in small groups or ‘harems’,
consisting of one male, one or two females and several
juveniles. The male fish is always the largest one in the group.
If the male is removed from the group (say, by fishing,
predation or old age), then the group’s dominant female
takes the former’s place – by changing sex and colour.
Within a couple of hours of the disappearance of the male,
the dominant female will start behaving in a masculine
manner. All western blue groper begin life as females and some, but
not all, change sex to males later in life. Biologists call this
type of change ‘protogynous hermaphroditism’, which is
very common for members of the wrasse family.
On average, female western blue groper take 15 to 20
years to reach sexual maturity, when they are around
650 mm in length.
Sex change in western blue groper occurs at a length of
about 820 mm and at an age of between 30 and 35 years.
This change in sex is closely associated with a change in
the groper’s colour from green to blue.
Western blue groper prefer to live in small groups or ‘harems’,
consisting of one male, one or two females and several
juveniles. The male fish is always the largest one in the group.
If the male is removed from the group (say, by fishing,
predation or old age), then the group’s dominant female
takes the former’s place – by changing sex and colour.
Within a couple of hours of the disappearance of the male,
the dominant female will start behaving in a masculine
manner. A couple of days later, the female’s colouration will
change to that of the male and within about 14 days her
sex will have changed to male. As a result of this change,
the other females will have moved up one position in the
social order of the harem, with a vacant position left at the
bottom for a new female member. |
评分
-
查看全部评分
|
漫谈女生在婚姻问题上更注重诸多“条件”？ (2007-8-16) 风万里 
楼主:pirate258
发表于 2023-1-9 16:16
