Here's a great post from Discoblog at Discover magazine on the complicated lives of wrasse. Who knew? An excerpt:
Starting life as females, bluestreak cleaner wrasse band together to
clean off parasites and dead tissue from bigger fish, including sharks.
At some point, the largest wrasse in a group, which typically has about
16 members, will change sex, become harem master, and reproduce with the others.
As Discoblog explains, it only gets more complicated from here. Scientists writing last year in The Proceedings of the Royal Society–Biology described how this large, newly-minted male keeps the rest of the group in line by punishing them when they over-eat. When a member of the harem eats too much tissue and mucus from larger fish that the group is grooming, she risks annoying the dinner host and driving it away. Further, if she eats too much, it increases the chances that she, too, will morph into a male and become a rival harem-master. So the large male has the task of "punishing" females who eat too much. In a series of elegant experiments, scientists demonstrated that the more a female eats, the harsher her punishment. Larger females, who are presumably closer to "turning" male are punished more severely than smaller ones, and punished females do eventually stand down and fall into line. The harsher the punishment, the more quickly the bad girls fall into line. The scientists demonstrated this in a really elegant experiment that you can read about here, at New Scientist.
I hope my husband doesn't read this.
(Via Discoblog and New Scientist)
–Mary Pinkowish
