The exact dates of evolution of shrimps are not known. But dating back to history, Triops cancriformis, one of the earliest forms of shrimps have existed from about 250 million years ago. Even after the dinosaurs disappeared from the earth’s crust, the shrimps were still existent. This was about 150 years hence. An amazing thing about these shrimps is that they are still so unevolved, that they are in the same state even on today’s date. Scientists have researched extensively on shrimps for a very long time.These crustaceans normally have 20 legs, but when just one gene was manipulated, shrimp with just three pairs of legs, like insects, were produced.
But this happened in nature hundreds of millions of years ago. Over time shrimps have evolved into species with the most colorful bodies. With time shrimps have evolved from just a ten legged crustaceans to various types which are Algae Eating Shrimp, Long-arm Shrimp, Ghost Shrimp and Fan Shrimp. Algae eating shrimp eat all forms of algae and they tuck themselves in plants. Long arm shrimp, although huge, are peaceful.They can be area controllers and will fight for food. Ghost shrimp are commonly used as live food, but are also a community fish. Fan shrimp are harmless scavengers perfect for community aquaria.
Shrimps mature and breed only in maritime habitat. Female shrimps lay from 0. 05 to 0. 1 million eggs that hatch into tiny nauplii within 24 hours. Naupliis breed on yolk reserves in their bodies. After metamorphosis they are converted to zaeae.
The second stage is algae and the third myses. Myses appear like tiny versions of fully developed shrimps which feed on algae. The process of hatching takes 12 days in all.