It is more common for two animals of different species to get fertile little ones together.
You may have learned that the definition of a species is a group of animals that can reproduce themselves.This might be the intention if a new animal is discovered and a discussion takes place whether or not it should be considered a separate species. But in practice you cannot apply that definition, because there is a need to classify the animal immediately, while it is not yet known whether or not it can reproduce itself with an existing species.
In addition, there are so-called ring species, so it can happen that A can reproduce with B and B with C, but A not with C. If we are talking about prehistoric animals such as H. Erectus, H. Neandertalis etc, that is even always so , because although a man cannot reproduce with a baboon, there is a chain of prehistoric species that connects us with the baboon and where each one can reproduce himself with his 鈧?艙neighbor/Vrouw 鈧?in the chain.
In short, you should not take the question of whether or not to hear the same species too seriously, especially when it comes to prehistoric animals.Because animals are simply classified on the basis of what is useful for the biologists, and the classifications are often a bit arbitrary.
That they are 2 different species, and they are not in this case, has less influence than they are of different sex.
In The nomenclature one maintains the following rule.
The name of an organism is 2-fold.Genus type name.For humans, this is Homo sapiens.Organisms of the same sex are basically intersecting. The offspring are not that by definition.
The genus and species are genetically determined by DNA (formerly a reasoned guess that was often correct).
As an example, We take a mule.
This is a cross of a horse stallion Equus cabalus with an donkey Equus asinus.For a mule it is reversed.The fact that both of the genus are Equus makes them able to cross.(Mules are infertile, mules are generally fertile)
For humans then Homo sapiens + Homo neanderthalensisapplies.Both are of the genus Homo.Some even believe that they are of the same kind, so it is even more obvious. Homo sapiens sapiens + Homo sapiens neanderthalensis.
A liger or a Teeuw?Panthera tigris + Panthera Leo.
What can normally not?Cheetah with Lion! Acinonyx jubatus + Panthera Leo!
And yet it succeeds between a sheep and a goat.Capra sp. + Ovis sp. This results in a GAAP or a scheit.
Some sexes do not allow this possibility of hybridization by allowing them to be sexually mature at other times or by making the genital organs incompatible.We see that for example in the genus Acronicta (butterfly).Attention creationists, this was not divine preconception, but simply an evolutionary consequence.
So the only thing that had to happen here was to put Homo sapiens and Homo neanderthalensis in the same period in the same zone and hope they had a sense in each other.And I would say, leave the chimpanzee alone. That’s Pan troglodytes + Homo sapiens and I really don’t want to see that result!
See likewise Neanderthal extinction.
An interesting question.Disclaimer: I am not an expert in evolutionary biology, but I am familiar with this biological rule. Individuals who can mix themselves and whose offspring can reproduce themselves (not a hybrid) are of the same kind.
That rule therefore assumes that Neaderthalers and Homo Sapiens are the same species!
So they are different subspecies, but the same species, not two different types!
Both Neanderthals and Sapiens are also descended from Homo Erectus.Homo Erectus is in turn descended from Homo Ergaster. Although there is a lively discussion about it within the scientific community. There are other scientists believe that Homo Erectus descenres from an Asian species and not from gay Ergaster from Africa. A theory that mainly finds many followers among Chinese scientists.
Moreover, there is another subspecies that has been mixed with the subspecies Homo Sapiens, namely Homo Denisova (found in Southeast Asia).
Moreover, there are two more descendants of Homo Erectus, namely Homo Heidelbergensis (spread over East Africa, South Africa, Europe) and Homo Antecessor (spread over Europe), but as far as I know it has not been mixed.What I do know is that of Heidelbergensis it is said that it also has subspecies, such as: Homo Heidelbergensis Heidelbergensis, Homo Heidelbergensis Daliensis, Homo Rhodesiensis and Homo Heidelbergensis Steinheimensi. There is one theory which states that Homo Sapiens is descended from the subspecies Homo Rhodesiensis.
What this means in any case is that much of the information in old textbooks is now obsolete.
The question then is what this means for us as Homo Sapiens.Do we have to call ourselves Homo Erectus Sapiens? Or Homo Neanderthalis Sapiens? Or Homo Sapiens Sapiens? I honestly don’t have a clue.
What it certainly demonstrates is that kind of deviation, the emergence of new species is much more gradual, than we sometimes think and that a lot of people (like) and more have in common than at first sight seems.
The less two individuals are related, the less likely they can reproduce together.If you were to try to cross a horse with a cow, no viable offspring would emerge. The DNA of the father and the mother is simply too different. With a horse and a donkey you still get offspring, but they cannot reproduce themselves. If the two types you are trying to cross are very closely related, the hybrids may be less good for plants, but there is still a certain chance that it can.If it is quite easy it is usually spoken of subspecies
So the limit is not as sharp as the taxonomen sometimes want to make us believe.Some paleontologists therefore prefer to talk about two subspecies of Homo sapiens sapiens and Homo sapiens neanderthalensis.Others find the differences between the two so great that they talk about two closely related types of Homo sapiens and Homo neanderthalensis.Remember that these differences in the skeleton were already known much earlier than the study of DNA.