Learn About Sponges: Quiz 3

Explanations for answers to sponge transplant quiz:

Different genotypes of sponge respond differently to different habitats.  This is certainly true, but the experiment uses transplants done with bits of the same sponges; hence, the genotypes are identical.

Adaptation of a genotype of sponge to a new habitat takes time.  Of course, and the data show that this may take from 4-18wks depending upon the direction of the transplant. But this does not explain the 4-week delay in response of the transplants after being moved to the low-energy environment.

For whatever reason, it takes the sponge longer to reduce the stiffness/strength of its new growth than to increase it.  If you clicked on this answer first, then you are good at scientific “baffle-gab”, for it offers no explanation of the data beyond what we see in the graphs.

The sponge is exhibiting a sort of “risk-assessment” in its response.  Yes, this is manifested as a delay in establishment of a stress-intolerant tactic on the part of the sponge (lower graph) and, as pointed out by the author of the study, is a unique finding for these primitive animals.  Palumbi 1984 Science 225: 1478.