how can Homo sapiens and Neanderthal be different species but Neanderthal dna is common in modern day people


To my 5 year old knowledge I thought Neanderthals were different species but for us to have part of their dna that means they got jiggy together and created fertile off spring with Homo sapiens but when a donkey and a horse do it they make infertile offspring? Are we not like actual separate species?

In: Biology

Just like dogs are all members of the same species and yet the multiple breeds can procreate and create viable offspring. Neanderthal extinction would be the equivalent of specific breed’s extinction.


Homo would be the genus which we share with them and others allowing us to mate with viable offspring being the product.

There were many different “breeds” of humans at one time. Only one species tho. So they could have crossbred. Some likely did like neanderthals did. Some maybe did not and went extinct without leaving rests of their dna in ours.

If two species are close enough together in an evolutionary sense they are sometimes able to breed. Think dogs and wolves or lions and tigers. We basically absorbed Neanderthals and cause their extinction by breeding with them

The way you are taught “what is a species” in school is a gross simplification

In nature, organisms do not adhere to strict rules. The high school level 1 biology class definition of a species is sorta accurate for many animals, but there are many many exceptions. There are genuses that produce infertile hybrids, sure, but there’s also things like “ring species” where geographically-adjacent species can each interbreed with their neighbor, but *not* the neighbor of their neighbor. And there are species in the process of diverging so there may be different populations that are becoming different sub-species

Humans and Neanderthals have a lot of differences, but those differences did not extend to differences in reproduction.

The DNA of 32 different hominids have been found in humans. Remains of only around dozen of those have been found by archeologists. The DNA of these different species is what caused the different races of humans. Geographic separation of sub-hominim DNA admixture markers prove humans races are at least different breeds, if not species. [](

According to the worlds oldest religious texts found so far (Sumerian), the different sub-hominin species around the world were uplifted by space faring beings to be a slave population for them. Who would have thought the ancient aliens theory is actually the worlds oldest religion?

Edit: Downvotes are because feelings are more important than facts.

Modern Humans are Homo Sapiens Sapiens. Neanderthals were Homo Sapiens Neanderthalensis. We are basically subspecies of the same species, or more akin to the distinction between a wolf and a domesticated dog (possibly even between breeds of dogs).