Voyage of the Cavalier or Have we broken Evolution?

Reading another blog (Thanks Leroy) reminded me of a discussion I had a while ago with Mr Midnite on Evolution.

Natural selection (survival of the fittest) describes how genetic variations within a population can lead to change (evolution). By chance some have a variation that leads to them being better suited to their environment so they survive and thrive better than others. Individuals that survive and go on to reproduce may pass these helpful characteristics to their offspring.

So say you took a population of a species and split them across two environments, dessert and swamp. If you could come back thousands of years later you should find that the changes that have allowed survival in each location are different. The descendants in the two locations would look different. For example the swamp dwellers could have developed webbed feet to help swimming. The dessert animals could have changed colour to give better camouflage from predators.

When it comes to humans we, Homo sapiens, are currently the only species in the homo genus. It looks like we evolved from the great apes into animals that used tools and spent more time walking rather than climbing. It is thought that we evolved from apes to:

Homo Habilis (nicknamed handy man) who had smaller molars, bigger brains compared to a great ape and used basic tools

Homo erectus, you guessed it he walked upright. Changes to the knees and skull (foramen magnum) were required to allow this and Mr H. Erectus did it. He may also have used fire!

Then around 250,000 years ago Homo sapiens arrived, they are characterised by greater skull expansion and ability to use more complex tools.

In my mind evolution goes
Miss H. Habilis – “oooh he tall and has bone tool, me love him, me want his hairy babies”
Mr H. Erectus – “Me tall man, me spread tall seed to hairy ladies”
And a few years later
Miss H. Erectus – “Oooh he tall, straight and has big head, he control fire and make good food. Me love him, me want his big head babies”
Mr H. Sapiens – “ Hairy lady, me like”
Research suggests that our DNA is more alike between individuals than in other species. There are some distinctive genetic characteristics caused by environmental factors, these include skin colour, nose shape and invisible changes like ability to breathe better at high altitude but generally we are all pretty similar.

So what now for evolution of man? Searching the web there is lots of evidence that human evolution is going at high speed while other evidence claims it has ground to a halt.

I happen to think we have broken evolution because we have stopped natural selection in the way Darwin saw it:
• Evolution is driven by natural selection and genetic mutation, the mutations not suited to the environment don’t survive. But in today’s world the majority of human offspring survive long enough to reproduce. Infant mortality is lower than ever and medical advancements mean that children who wouldn’t have survived 20 to 30 years ago now live into adulthood.
• In recent history (hundreds rather than thousands of years ago) the powerful and successful men would have many legitimate and illegitimate children. Now well I’m going to go out on a limb and say I think (with no evidence to support it) that powerful and successful people have less children.
• Evolution seems to like isolated populations; these populations are more inclined towards random change. The world has become so connected that changes of random change are now very low. Also inbreeding is less likely by either mistake or intention. In fact we are much more likely now to get together with someone from a different ethnic group creating diversity but not powering evolution.

So natural selection has lost a lot of its power. Maybe man as we know him today is the same as man will be in thousands of years.

But perhaps natural selection is working in a different way. Survival of the fittest isn’t exactly the right way to describe natural selection because the fittest are not always the best adaptation for the environment. Examples I have spotted in my browsing include Neanderthal woman who could have kicked Terminators ass (sorry Arnie) and prehistoric Australian Aborigines who it is thought could easily take the modern 100M record.

People who reproduce most will determine the next steps in evolution because it is their genes, mutations and all that will be passed on the most. So who in our society reproduces most?
• It’s not your skinny size 0 models that the media flaunt before us as perfection. Low body fat prevents ovulation so they are much less likely to reproduce. Plus baby weight, stretch marks, I think not.
• What about the role models in our society? World leaders, actors, sports stars, pop stars? Well it looks like most will have a kid or two but there seems to be a new hobby to adopt one of each colour, “gotta catch em all” as they say.
• Industrial leaders, top business men and women, CEOs, Innovators etc? Most will have put their career first so probably looking at low birth rate here too.
• So what does that leave? The Jerry Springer section of society? You know the ones, you see them on Jerry’s show, Tricia, Maury etc. It usually goes something like “I know he’s my babies daddy, I ain’t never been with anyone else, see the baby looks like him, it’s his nose innit” closely followed by the proclamation “you are not the father”. I think we have a winner.

Yes they are reproducing, surviving and thriving. Physically the women are fertile, not too thin, not too fat. They are perfectly adapted for their environment but there is scope for evolution. I’m thinking of an increase in the ability to scream obscenities, better developed thumbs for game play and perhaps better vision and hearing for picking up the gossip.

Guess I’ll just have to pop back in 50,000 years and see what everyone looks like then.


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30 something female, GSOH, independent, unreliable, seeks sanity. Must like dogs and handbags!