January 02, 2013 | Graham

What has become of human evolution?

Evolution occurs in response to environmental pressures, but what environmental pressures are there left to operate on man in such a way that he might continue to evolve when we have a cradle to grave nanny state whose duty is not only to protect him, but to find cures for all defects, even those caused by his DNA?

Faced with this question I long ago came to the conclusion that man might be one of the first species to experience what you might call negative evolution – a species in which his actual body became less adapted to his environment, even though, by externalising properties of his body he will actually come to dominate environment more than he does even at the moment.

However, some recent observations have caused me to muse about whether, while the whole species may be likely to physically deterioriate, some parts of it may still be subject to evolutionary pressure. In making these observations I am not thinking of those few remnants of man still dominated by their environment, but in fact those tribes that inhabit the highest spots in the modern environmental ecosystem.

The observations to which I refer are reports that cane toads are evolving faster than thought, over as few as 50 generations. The other is an anecdotal sampling of the student populations at two Brisbane high schools with quite different socio-demographic bases.

Cane toads are apparently becoming stronger and longer-limbed. The evolutionary theory here is that only the fastest toads are at the forefront of the toad invasion, and they tend to be long-limbed. As a result their mates are also long-limbed, and the species evolves as their offspring are more likely to be long-limbed also. This is not to say that all toads have evolved like this. Presumably the more home-bodied toads have stayed much the same, mate with other home-bodies, and produce undistinguished progeny, but in the areas where toads first established themselves.

The point here is that species may evolve into subspecies, and thus may evolve to a point where they become distinct species. Cane toads may be on this trajectory, at least temporarily.

My partner’s daughters are both willowy beauties. Over twelve months ago they moved from a school in a lower-middle class area to one of the two or three best state schools in Brisbane in one of the highest socio-economic catchments. At their old school kids were continually asking them why they were so thin. At their new school, while I’m sure they still stand out, leanness is the order of the day.

We know, at least in Australia, that obesity and low income tend to run together. We attribute this to poor education, and cost pressures, leading to overconsumption of calorie-dense foods, like Macdonald’s. But could it be more complicated than this?

Could part of the reason be that people in higher socio-demographics select mates for intellectual and aesthetic reasons tied to the urge to succeed? As we know again that good looks help us to succeed, are this subset of our species selectively breeding not just more successful offspring, but offspring who are more likely than others to have a biology that favours good looks, of which leanness is an integral part?

Are the obese and over-weight to some extent victims of negative evolution? Something to think of over the leftover plum pudding, especially if you think fat taxes and “Life. Be in it.” campaigns are the answer.


Posted by Graham at 10:04 pm | Comments (3) |
Filed under: Uncategorized


  1. I think eventually we are going to see genetic engineering of humans anyway.ie accelerated evolution.

    There will a huge difference between the super intelligent elite and the masses.This will bring about enormous social conflict.Robotics will make a lot of human labour obsolete and hence in some elite circles , they already refer to us as ” The useless eaters”.

    They will also be able to slow the ageing process hence population pressures will increase.

    Unless we all develop proper constitutions limit the power of our Govts and the Corporate interests which greatly influence them,the future could be an Oewellian nightmare.

    Comment by Ross — January 4, 2013 @ 12:49 pm

  2. No amount of genetic engineering or medical intervention is going to enrich our gene pool. And because of medical intervention the developed world will begin to decline in the evolutionary cycle. The survival of the fittest still runs true. I am referring to our gene pool. An adult from a 3rd world survived against all odds purely by the strength of his genes while the weaker gene diapered(ie not living long enough to reproduce). The diversity of strong and adaptable gene pool is greater in poorer nations while the dilution of the gene pool and the propagation of weak genes is greater in developed countries. What is the solution? Cross breeding is the answer!! Nature shows us the way… cross pollinated plants are better, more diverse and much stronger than self-pollinated ones.

    Comment by Jolly — January 7, 2013 @ 3:53 pm

  3. Jolly,it has already begun.Right now they are on the cusp of eliminating the bad genes that ail our humanity.This also means positive genes can be added.

    Consider also the imput of micro computers in our brains that enhance our memory and speed of thinking.

    Cross breeding with those in poor countries who have disease resistance and physical prowess is just part of the equation.It may not enhance intelligence. Yes the inbred royals needed Dianna Spencer to diversify the gene pool,but soon individual genes will be able to be manipulated and changed.

    Where human spirituality and the soul comes into this,I have absolutely no idea.That’s why the debate needs to happen now.

    Comment by Ross — January 7, 2013 @ 7:51 pm

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