BIOLOGY 2F03 Lecture Notes - Mayfly, Trematode Life Cycle Stages, Schistosoma
Document Summary
Good food for pretty much everyone who is the right size in lakes. Other defensive mechanisms: assume a posture that makes them bigger, points tail over their head like a scorpion. By assuming a scorpion posture, ephemerellid mayflies may make themselves appear larger. Mullerian: trying to resemble somebody who is very unpleasant. Aposematic colouration: changing colour, yellow, black, red have been adopted as the warning i am not edible, mimics try to look like them to deceive potential predators sea horse resembles algae. 5 different species, swimming larva: cercaria, they have a very complicated life style. Debilitating parasite, complex life cycle, easy re-infection. Millions affected: can ecology help, get rid of snails to break the cycle. Distributions of snail hosts and crayfish introduced american crayfish eats the snail, host of flukes. Most ponds have either snails or crayfish but not both. Only a few ponds have both organisms. Potential for reduction of infection by schistosoma.
