Perhaps they are all the same species

[Calpalned]

1) The most popular credence is that Homo

Erectus/Ergaster gave rise to Homo Heidelbergensis, which in turn is

the ancestor of the Neanderthal. However, each of the species I

mentioned, to me, appear pretty much the same. They all have weak

chins and brow ridges. Their face shape generally stays the same.

The only difference is an augmentation in brain size. Why are they

considered different species?

 

[Simon Bridge]

Taxonomy issue ... you want to know about cladystics.
http://www.ncbi.nlm.nih.gov/pubmed/19249816
http://anthropology.net/2008/05/06/a-cladistic-analysis-of-17-hominid-skulls/

 

[zoki85]

1) The most popular credence is that Homo

Erectus/Ergaster gave rise to Homo Heidelbergensis, which in turn is

the ancestor of the Neanderthal. However, each of the species I

mentioned, to me, appear pretty much the same. They all have weak

chins and brow ridges. Their face shape generally stays the same.

The only difference is an augmentation in brain size. Why are they

considered different species?

Well, Pygmies and Mongoloids appear pretty different to me. And yet they belong to the Homo sapiens species.

 

[Calpalned]

Well, Pygmies and Mongoloids appear pretty different to me. And yet they belong to the Homo sapiens species.

So it is clear that people who look quite different are grouped into the same species. But ironically, people who look similar (at least according to their skull and bone shape) like homo erectus, neanderthal, heidelbergensis, antecessor etc, are split up into different species. This is so odd.

 

[zoki85]

So it is clear that people who look quite different are grouped into the same species. But ironically, people who look similar (at least according to their skull and bone shape) like homo erectus, neanderthal, heidelbergensis, antecessor etc, are split up into different species. This is so odd.

Let genome be fair judge here since eye can be misleading

 

[Pythagorean]

I agree with zoki85. We might think whales were a type of big fish if we judge only by morphology, but whales descended from four legged land animals. What we have here is what's called "convergent evolution". Different species can evolve the same trait (in this case fins) independently.

 

[Calpalned]

Thank you zoki85 and Pythagorean