1. Evolution By Natural Selection = Glitter And Glue
The Tricky Bit Adaptive evolution by natural selection is based on the presence of heritable genetic variation creating differing levels of fitness between individuals. Fitness in this context doesn't just mean top notch cardio, but more a quality of being "fit for purpose". If a random genetic mutation in an individual turns out to produce a beneficial trait that will ultimately result in reproductive success, then that trait is more likely to be passed on to the next generation and subsequently propagate throughout the species to become the norm over a period of time. On the flip side, mutations that are detrimental to survival will make the individual less likely to reproduce and pass them on. This doesn't just refer to new mutations, as a change in the environment might render a previously advantageous adaptations redundant or even a liability. For every advantageous or deleterious mutation, there are also countless random mutations that have no impact whatsoever on the individual's ability to mate. The Simpler Way The analogies for evolution come in two parts, one for the evolution part and one for the natural selection part. It's easy to think that the evolution of, say, humans from fish as such an impossibly huge leap that it's not possible. However, the tiny mutations and adaptations happen over such an incredibly long period of time so as to be virtually imperceptible. Take a look at this colour gradient, for example. It is impossible to pinpoint the exact point that it changes from red to purple or purple to blue, and yet, the two ends of the spectrum are drastically different from one another. Each pixel along the spectrum is also different to the one next to it, but in a tiny, imperceptible way. These adaptations are all very well, but they've got to stick around and natural selection is the driving force here. Evolution is not "goal oriented", so a giraffe will not see high branches and grow a longer next, but the ones with the longer necks tend to stick around because they are fitter for purpose. Imagine you have a sheet of paper and you draw a picture in glue on it. You then completely cover the paper in glitter, you can bury the damn thing in it if you want, but when you pick it up and shake it off, the only glitter that remains will be the bit that happened to be in the right place at the right time and stuck to the glue. The other glitter was superfluous and random, the stuff that stuck was the only glitter that was fit for the purpose of creating your beautiful glitter art, and it was completely by chance. Does science make you tingle in your special place? Like us on Facebook or follow us on Twitter for plenty more.Want to write for WhatCulture Science? Click here to find out how you could get paid to write about what you love.
