A Smorgasbord of Cichlids
Why are there so many species of cichlids? Dr. Melanie Stiassny, a scientist with the American Museum of Natural History, has done lots of research on African cichlids. She thinks their success has something to do with the way they take care of their young. Most fish species simply leave their eggs to develop on their own. But cichlids look after their young until they're big enough to live on their own. In fact, many cichlids are "maternal mouthbreeders," which is a fancy way of saying that the female carries the fertilized eggs around in her mouth until they hatch and are ready to swim free. Even when the offspring are old enough to swim on their own, they return to her mouth when predators are near, or to sleep. Since cichlids tend to stay with their young, they tend to stick together and are often isolated from other fish. This isolation means that over many generations, they evolve (change) faster than other fish. This may explain why there are so many unique species of cichlid.
Family: Cichlidae
Size: varies from one inch to three feet long
Habitat: freshwater habitats in South and Central America, India, Madagascar, and Africa
Diet: varies by species, but may include algae, plants, insects, or fish
Characteristics: single nostril on either side of the head, long straight line of scales divided into two rows along the sides of the body
Cichlids have a variety of diets. Some cichlids are "piscivores." If the prefix "pisci" means "fish," what do you think piscivores eat?
pie
plants
other fish
Correct!
While piscivores eat other fish, some cichlid species eat plants, others eat insects, and still others eat algae. In fact, some species even eat the scales off other cichlids!
One type of cichlid catches prey by playing dead on the lake floor.
Fact
To trap its prey, one species of cichlid sinks to the bottom and lies still on its side. Then this cichlid catches any unsuspecting fish that approach.
One cichlid species is so thin it can hide from predators and prey simply by turning to face them.
Fact
It's true! Dimidiochromis comprecessips is as thin as a pancake. By turning to face its prey, it's almost invisible. Pretty handy when sneaking up on dinner!