A model organism is a species that has been widely studied to understand a particular biological phenomena, normally used because they are easy to breed and maintain in a laboratory setting and has certain experimental advantage.
The criteria that Thomas hunt Morgan was looking for include; the model organism should be small in size, easy to keep in the laboratory and also able to produce large number of off springs in a short time.
By time......................
-In Africa savanna more wildebeest are born than the environment can support. As a result over a period of years individuals that are well suited to the environment reproduce, and those that have lesser adaptations die before they reproduce. This is referred to as natural selection.
