[redfreedom]

Hmmm, inbreeding? So when the good Lord put us on Earth is it possible those creatures thought of as being links between chimps and man were just deformed inbred idiots?

[qwertyz]

Highly recommended ... the must-see comedy satire for our times ... Idiocracy ... free at https://archive.org/details/Idiocracy_201507

[BipolarBob]

Genetic engineering in the early part of human history. Including interspecies breeding. These experiments were prone to failure.

[Cronos]

The Neanderthals were NOT a "link between chimps and man".

There is no species that is a "link between chimps and man" per se --> what is more correct is that chimps (genus PAN) are, what you may call "fourth cousins" to Homo Homo Sapiens (humans)

Modern Humans (Homo homo sapiens) and Chimps had a common ancestor millions of years ago

Within the "Homo" genus, we have homo sapiens and homo neanderthalensis - which could to some extent interbreed (most results were sterile, but not all) - which is why all NON-sub Saharan AFRICANS have some levels of Neanderthal genes.