I'm not saying that it's completely normal, but that does not mean that it is not uncommon. I don't think that the reason your gerbil's tail fell off was because of the jagged area, but because your sister pulled him by the tail. You should NEVER do this. If you do, the tail will either deglove or just break off.
Fish Spawning. Female fish lay eggs, with the eggs being fertilized by the males in close attendance. Eggs develop more rapidly (in a few weeks) in warmer temperatures, and more slowly in colder water (up to months).Most freshwater fish spawn in the spring, although salmon, char, and some trout spawn in the fall.ish Spawning. Female fish lay eggs, with the eggs being fertilized by the males in close attendance. Eggs develop more rapidly (in a few weeks) in warmer temperatures, and more slowly in colder water (up to months).
Echinoderm spawning events often set off feeding frenzies in the fish and coral communities. After spawning, a few species of echinoderms will care for their fertilized eggs, most commonly the cold water starfishes. Asexual Reproduction. The most common form of asexual reproduction in echinoderms is a process known as fragmentation.