A species is a group of organisms that interbreed to produce fertile offspring. Selective breeding is when organisms are deliberately bred so their offspring have the desirable characteristics.

English Bulldogs are loving family dogs. But as a breed they suffer from health problems Crossing the English Bulldog with another breed is the best way to ensure its survival, scientists have argued.

Pure-bred dogs have been regarded as superior to crossbreeds or what some people refer to as mutts. However, we now ...