Sentence examples for could not breed from inspiring English sources

These animals could not breed together on their own?

As the researchers began the test, they faced an unexpected problem: they could not breed mutants.

So, of course, this organism could not breed true, because its reproductive cells would be either one type or the other.

This two-locus, two-allele model is the simplest we could conceive; a single locus, with parents fixed for alternative alleles, would be insufficient because hybrid lineages would be heterozygous and could not breed true.

In North American zoos, for instance, several of the 29 captive specimens in 2008 were hybrids that could not breed while most were past their reproductive years, and the last captive birth was in 2001 at the San Diego Zoo.

If Knut couldn't breed, so the argument went, what was the purpose of keeping him in captivity?

Most of the fish brought in were juveniles -- under three years old -- which meant they couldn't breed for another 10-15 years.

The approach has been used before with corn and other plants but is met with resistance by environmental groups and a skeptical public that doesn't like mixing creatures that couldn't breed naturally.

Its keepers mistook it for an olinga - a close relative - and could not understand why it would not breed.

Named for Kelso Everett, a friend of Mrs. du Pont's, he won 39 times in 63 outings, racing until age 9 because he could not be bred.

The ban had been imposed only because tigers could not be bred in captivity, they said, but now they can be.Conservationists are campaigning against allowing farmed-tiger parts to be traded.