It may not be 100% accurate but I think it's reasonable to describe colloquially any changes or adaptation within a species as evolution. Clearly the same process is at work.
You are more of an expert about this than you let on Fran . You are right that adaptation and natural selection are not the same thing, but both in combination lead us to gradual evolution. An interesting example in humans is lactase persistence, allowing us to drink non-human milk as adults, which only evolved around 10,000 years ago. Darwin Awards are another. I don't know anything about the improved intelligence across generations, I could certainly believe that education methods have improved over short time scales.
Evolution is generally a slow process...sometimes species are lead into an evolutionary black hole and die out if circumstances change. Most marked changes which occur by chance (called sports) are disadvantageous and the offspring are usually aborted or die young...it is rare that such a change is advantageous....but if it is, it becomes a powerful force for change being greater than the normally slow changes. In flowering or edible plants, gardeners look out for sports and they breed from them if they like them. On the other hand they destroy them if the change is disadvantageous. However, generally gardeners produce the desired characteristics by cross-breeding.
What about the Finches on the Galapagos? It was enviromental pressures (on each Island) that resulted in adaptations becoming successful so as the birds (one species initially) could survive on the various islands in whatever niche they filled there. So the inheherited changes (adaptations) over time culminated in a new species. Isn't the adaptations of these Finches a process of natural selection? I'm no expert, but is that not evolution? Is this about the definition of adaptation I wonder? There are behavioural adaptations and genetic adaptations, maybe one results in the other in some cases.
I think it's pretty reasonable to conclude that growth of the brain and the increased intelligence this brings would have evolved significantly over 1000s of years. Of course the difference between a child and their grandparent(from which this topic originally adapted from) would be negligible. I have seen many experts who believe that the next species of Humanoid is likely to be the 1st ever to have gained control of their own evolutionary path. Whether this leads to X-Men style results is another matter
The Finches are a good example. They all originated from one population and got carried or blown to the variou Islands. These islands have different vegetation. Perhaps during a bad year for weather or disease, their preferred food source is very scarce. There is another plant which produces nutritious seeds but they are encased in a tough seed pod. There is range of different beak shapes and sizes in the finch population. Only a small proportion of birds have beaks strong enough to break open the pods. Their smaller beaked fellow birds starve, whilst they go on to successfully reproduce. That process is natural selection, the survival of the fittest. Evolution is the cumulative effect of lots of natural selection changing a population over time. Evolution is a timeline thing; one population of organisms have changed from one species to another.
Accidental random events may be a tool of evolution, but is not a definition of the term. Favourable random events may become hardwired if they increase survival to breed, but evolution mainly involves the favouring of a characteristic that already shows variation in the population (i.e. adaptation). For example, daisies flower on shorter stems in a lawn than in a meadow, because in a lawn only short varieties get to seed. If the lawn is allowed to turn into a meadow, taller daisies are favoured. This is reversible because the daisy still has variations in height. When animals and plants go too far down one path they become a hostage to fortune and may die out should conditions change. More developed animals such as mammals don't have time to change if conditions alter suddenly...they then become extinct (this has happened for millennia...not just recently).
Read "The Greatest Show on Earth" if you want to understand all this. Richard Dawkins is one of the clearest and coherent authors I have ever read. Vin
Read his collected works. Perhaps start with Unweaving the Rainbow. If that doesn't get you loving Science, nothing will. Off topic? Ssshhhhhh! One the mods will hear you...
All this is clearly bollocks as there is a man in the sky who created us all and there's no evidence to disprove that...
I do agree but having read pretty much every word he's written for print, I know that it comes from a deep passion for the scientific method. I also get the impression he's pretty exasperated with having to repeat the same arguments against creationism every time he tries to discuss evolution. When you have 40% of americans believing the world is under 10,000 years old, I can see where exasperation might become a problem. So I can understand his militancy but I agree that it doesn't make it any more bearable. Vin
Sorry Fran - using the phone and trying to snip to save space. Amazed at the discussion. I have a degree in Zoology and Oceanography and may have got my understanding about adaptation mixed up but I understood both adaptation and evolution depend upon genetic changes. I don't believe we would want to say black humans evolved into white humans but the species adapted over time via genetic mutations being favoured by survival caused by environmental pressures? (Slightly worried I'm bordering on racism here?) My brain hurts. BTW I am probably need to out myself as a Christian and believing in a creator God etc. but currently am undecided about whether evolution from one kind to another has happened or simply that creation over time along with extinction and adaptation is another way of interpreting the current data. Until we create life from chemicals or record evolution happening it will still be just another theory to me.
Really no need to worry on the racism card (speciesism might be a different story!) Black and white humans are both humans. The fact that black Africans are earlier chronologically than white Europeans is beyond doubt but they are not a better species, just a later variant.
Definitely not racism. There was an article in the Economist only last week reporting research to suggest that the reason for black skin is related to the need for protection against skin cancer as we evolved to lose our body hair (a shaved chimpanzee is white, who'd have thought?). Then a different evolutionary pressure took over as humans moved towards the poles, namely a need for lighter skin to allow synthesis of vitamin D. Vin
