What aquatic ecosystem is likely to be the warmest?

Coastal at the temperate latitude, basically the deeper you go, the colder it is...excluding the sulfer volcanoes but I don't think those apply

small, big, or no change could occur in the phenotype. it could cause something as simple as a cats ears to curl backwards or something as frighting as death. it could also occur in the protien-coding area and have an effect on that but no effect on the amino acids. what has to occur is a changing in the hox gene or the control gene.

b.have there own function.