Are we hybrids?

Dr. Eugene McCarthy, a Ph.D in Genetics and an expert in hybridization, speculates in Human origins: Are we hybrids? that human beings are the result of hybridization between chimpanzees and pigs. 

A hybrid is produced when two different species mate and produce offspring. Mules are the result of a mating between a male donkey and female horse. Ligers the result of a mating between lions and tigers. Zedonks the result of a mating between zebras and donkeys. Hybrids are not always infertile and fertility can be improved by successive backcrossing with one of the parents. McCarthy speculates that humans may have been the result of the mating of a male boar with a female chimpanzee and that successive matings within a small population gave rise to humans.

McCarthy’s evidence for this is primarily morphological and not genetic.  He claims that the multiple generations of backcrossing between pigs and chimpanzees would effectively mask any contribution from pig in nucleotide sequence data. His article lists the similarities between pigs and humans and where humans and pigs differ from nonhuman primates. In his list are included: a layer of subcutaneous fat, thermoregulatory sweating, normal host for the human flea , epidermal lipids contain triglycerides and free fatty acids, lightly pigmented eyes common, eyebrows, heavy eyelashes, earlobes. more lumbar vertebrae, fewer sacral vertebrae , centralized spine, sides of pelvis turn forward, diverticulum at cardiac end of stomach, multipyramidal kidneys, hymen, absence of periodic sexual swellings in female, nipples low on chest, brain lobes (frontal and temporal prominent), primitive premolar, nocturnal activity, extended male copulation time, female orgasm, short menstrual cycle, and tears. Also things common to humans and pigs and rare of absent in nonhuman primates are heart attack, atherosclerosis, and melanoma.

Since McCarthy’s evidence is not genetic, it might simply be that the similarities between humans and pigs are the result of convergent evolution instead of cross-breeding. In other words, the common features are the result of parallel evolutionary processes possibly the result of similar selective pressures. Once humans split from chimpanzees and were forced to adapt to a more terrestrial environment, humans evolved characteristics similar to  pigs.

Advertisements
This entry was posted in Brain size, Human Evolution. Bookmark the permalink.

6 Responses to Are we hybrids?

  1. Marilyn says:

    I will try to keep an open mind here but somehow even though I believe in the evolution of a species, this takes it to another level that my logical or spiritual mind cannot comprehend. Interesting though it is to read. Thanks for the post.

  2. James Cross says:

    I must admit I am having a hard time accepting this theory but I think it is at least possible.

    In addition, it appears that the way new species develop is a little more complex than the usual view of random mutation + natural selection approach found in the textbooks. I will posting a link to another article soon that shows that some species appear to have evolved by incorporating the genetic material of other species. There has also been speculation that the the mitochondria found in cells with nuclei may have originated as bacteria that was assimilated and began living in symbiosis.

    The author of this theory has a whole book documenting avian hybrids.

    So it looks like life has a lot of different ways of multiplying its complexity.

  3. me@gmail.com says:

    Even if wrong, the theory has some evidence on his favor, that requires scientific backed answers. And questions are good for science.

  4. Steve Garcia says:

    I had read this a short time ago and am glad to see someone else giving the speculation serious consideration. It’s hard to argue with him. I DO think his hybridization background includes a lot of DNA overlap, so even though he is not (to my knowledge) bringing DNA into it right now, that’s not to say that he won’t. I’ve seen people rip into it on several different fronts, and they should and will continue to. At the same time, he may, in the end, prove correct – as correct as science can be.

    Years ago when I first herad of “junk DNA,” I thought I was going to puke. The DNA researchers were less than 5 years past the human genome project and already were ready to say they knew everything there was to know about the genome – and that 90%+ of it was worthless crap. A few years back I read where someone had seen a purpose for some of the segments in the supposedly junk DNA. There are VAST numbers of long segments of DNA in the human genome that we have yet to figure out. It should be likened to the discovery of America – just because you’ve settled one portion of it doesn’t mean you know anything about what is over the next hill.

    It is entirely likely that the pig DNA – if it exists – is somewhere over that hill, somewhere in the unknown DNA they call junk.

    I wouldn’t put down qualitative evidence, either. If nothing else they can be pointers to places in the genome. And if they point and fail, it may not be disproof, because those vast tracts could hide certain DNA from our search for a long time. Certainly if no one is looking for it, they won’t likely find it.

    I’ve shared this with some other good minds, and all of them have come back scratching their heads – and wondering. One of them even goes around now, wondering which people are pigs and which are chimps. I admit I look for pig traits now myself. Including my own gut that shouldn’t be there based on my caloric intake over a long period of time.

    I’ll really be in trouble when Miss Piggy starts looking good to me…LOL

  5. James Cross says:

    Thanks for commenting.

    You know the saying about extraordinary claims and evidence. I would really like to see some DNA evidence or something beyond morphology before I buy into it but, like you say, it deserves some consideration.

  6. Pingback: Life Gets Complicated | Broad Speculations

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s