Evolution - Recommend a good book

Dr Pepper

Hi,

I know this is not exactly A & A but I've often seen the subject mentioned on this forum so...

I'm looking for a good, interesting, beginners-ish book about Evolution. I already have a good understanding of the basic mechanisms of it but would like to have a closer look - In particular, I am interested in finding out how we got from a lifeless chemical soup to cells that were able to make exact (or not-so-exact at times) copies of themselves. I'm obviously a firm believer in Evolution but I've found it increasingly difficult lately to imagine how these first steps could have happened! Anybody know a book that fits the bill?

PS - I'm not the best reader unfortunately so the lighter/easier-to-read it is, the better. (I am trying to improve )

robindch

> I am interested in finding out how we got from a lifeless chemical soup to
> cells that were able to make exact (or not-so-exact at times) copies of themselves.

There's no book that I'm aware of which covers this at beginners level, because the area is still the subject of a lot of active research and even if it weren't, it's not a beginner's level topic within organic polymer chemistry anyway. For the moment, the web is the best place to get a basic understanding of where research is currently at:

http://en.wikipedia.org/wiki/Origin_of_life
http://nitro.biosci.arizona.edu/courses/EEB105/lectures/Origins_of_Life/origins.html
http://www.resa.net/nasa/origins_life.htm

If you're prepared to leave abiogenesis aside, then you may enjoy Dawkins book "The Selfish Gene" which explains the current understanding of the modern evolutionary synthesis rather well.

aidan24326

Dawkins book 'The Blind Watchmaker' is also very good and not overly technical (i.e someone with a reasonable grasp of the subject would be able to handle most of it pretty well). Although the book is mainly a treatment of natural selection processes, I reccomend you read Chapter 6 for a fascinating look at how replication with selection can occur in even relatively simple inorganic material. Speculative but thought provoking nonetheless.

Beruthiel

Dawkins also wrote The Selfish Gene, which is a good read.

Dades

Bill Bryson's "A Short History of Nearly Everything" devotes some time to evolution. It's written in a very reader-friendly way.

Although when I read it I almost got the impression Bryson himself was unconvinced about the whole 'evolving from chemical soup' thing.

pH

The actual explanation of the origins of the first self replicating chemicals is likely to be a highly technical affair, and probably not that interesting in my opinion.

I found Dawkin's The Ancestor's Tale an extremely satisfying read, I just cannot imagine anyone reading it and still not accepting that 'evolution happened'.

aidan24326

pH wrote:

I found Dawkin's The Ancestor's Tale an extremely satisfying read, I just cannot imagine anyone reading it and still not accepting that 'evolution happened'.

About halfway through that one myself. Typically excellent Dawkins and I would echo your reccomendation of it.

Dr Pepper

Thanks very much for the tips folks! I will try to get to them all starting with "A Short History of Nearly Everything" which I've heard lots of good things about.

IFX

Dr Pepper wrote:

Thanks very much for the tips folks! I will try to get to them all starting with "A Short History of Nearly Everything" which I've heard lots of good things about.

I am actually reading 'The Blind Watchmaker' by Dawkins at the moment, I don't think it's that good. It's just ok.

Guest

This is sort of a tangent question to the OP's query.

Maybe someone can recommend a book or even some links.

I understand natural selection, but I'm not crystal clear how it works at a DNA level. How does DNA know when to mutate with regards to the host's natural environment (Climate, altitude)?

If a host reproduces / replicates later on in its lifespan, do the genes then know the environment better in which they need to adapt?

Does the double helix mutate when a sperm meets an egg and an offspring is formed?

These questions should hopefully give you an idea of where my haziness lies. Does Dawkin's Selfish Gene go into this sort of detail?

I'd appreciate if someone could point me in the right direction.

Thank you

bonkey

() wrote:

I understand natural selection, but I'm not crystal clear how it works at a DNA level. How does DNA know when to mutate with regards to the host's natural environment (Climate, altitude)?

Mutation is random. Natural selection takes care of the rest.

I'd appreciate if someone could point me in the right direction.

Strange though it may seem, the mathematical field of GA (Genetic Algorithms) can give surprisingly good insight into how random mutations coupled with a "fitness assessor" can achieve results. While not entirely comparable to natural selection and genetics, its not without merit.

Having said all of that, if you understand natural selection (as you say), then you should be able to understand how random genetic mutation can function as a "driving force" for the system.

Zillah

() wrote:

I understand natural selection, but I'm not crystal clear how it works at a DNA level. How does DNA know when to mutate with regards to the host's natural environment (Climate, altitude)?

DNA makes completely random changes to the genes. 99% (arbitrary number...) of these are absolutely lethally disastrous or completely irrelevant for the animal. The 1% that get a bonus are more likely to survive and so those genes spread. The ones that got bad mutation (the vast majority) die horribly and so their genes vanish quickly.

Does the double helix mutate when a sperm meets an egg and an offspring is formed?

My memory is a little rusty on the technicalities but I'm fairly sure the only relevant mutations take place when the sperm/egg are formed and when they join. Someone will no doubt correct me if I've misremembered.

Scofflaw

() wrote:

I understand natural selection, but I'm not crystal clear how it works at a DNA level. How does DNA know when to mutate with regards to the host's natural environment (Climate, altitude)?

Mutation doesn't happen particularly when organisms need to change. DNA mutates all the time, wherever the organism is and whatever it's doing, whether it's well-adapted to its environment or not. Chemicals, cosmic rays, replication, are all mutagens. The DNA doesn't get a say in the process - it's random.

What does change if the environment changes are the 'selection pressures' - that is, the ferocity with which the unfit are weeded out.

So, if you're talking about a species in which every adult has 10 offspring, then if there are low selection pressures, say 8 of them will survive to breed. If the environment has changed, and selection pressures have increased, maybe only 4 will survive.

Say the climate has got drier, and one of the 10 initial offspring has a heritable mutation that increases its ability to go without water by 10%, then that's a 10% advantage, so that particular individual is 10% more likely to be one of the survivors - and its offspring, in turn, are more likely to survive. Does that make sense?

So, what evolution works on is the natural variation between individuals that is provided by constant mutation.

() wrote:

If a host reproduces / replicates later on in its lifespan, do the genes then know the environment better in which they need to adapt?

Hmm. Not as far as is currently certain, no. The later in life a host reproduces, the more likely it is to produce mutant offspring, because the more time it has had to accumulate heritable mutations. The mutations it has accumulated, however, will be nothing to do with the environment.

There is some evidence from current research that suggests various mechanisms (called 'epigenetic' mechanisms) may allow for a certain amount of feedback from the environment. Even so, though, the organism is not in control of its mutation rate.

() wrote:

Does the double helix mutate when a sperm meets an egg and an offspring is formed?

Not particularly, no. What happens at that point is recombination of the DNA from the two parent - the DNA is shuffled and recopied. Sometimes this does result in particular types of mutation caused by copying errors ('frame shift' mutations, for example, where all the DNA bases get shifted by one or two bases all the way along).

What is important about this is that only mutations in the 'germ cells' (ie the reproductive cells) can be passed on to offspring. If a cell in your finger mutates, it may become a cancer, but it certainly won't get passed on to your offspring. If a cell in one's testicles mutates, however, that mutation may wind up in a sperm, which means it will be passed on to the offspring.

() wrote:

These questions should hopefully give you an idea of where my haziness lies. Does Dawkin's Selfish Gene go into this sort of detail?

I'd appreciate if someone could point me in the right direction.

Thank you

Like most of us, I find it hard to think of a good book off the top of my head. I would think a decent biology primer would cover it, particularly a University-level one.

cordially,
Scofflaw

robindch

> I understand natural selection, but I'm not crystal clear how it works at a
> DNA level. How does DNA know when to mutate with regards to the host's
> natural environment (Climate, altitude)?

The good folks above have written longer answers than I've time to write here, but you're getting things back-to-front in saying that "DNA knows when to mutate" -- it doesn't -- it's just random changes, but applied in a selective framework. It may be easier to think of evolution in terms of a joke rather than DNA: say you hear a good joke and you tell it to a few mates over a few beers. Your friends then retell the joke later on to more friends. Some will tell it better than others, and it's more likely over time, that the better-told versions of the joke will spread, rather than the badly-told versions. Same with languages, musical tunes, religions -- the ones which spread are the ones which are more appealing than the less-appealing ones.

The core idea is that things change as they get passed on. And as they change, they are either better or worse suited to where they turn up. Most of the variations are worse, but just a few will be better, and they'll be the ones which will out-breed the others.

In answer to your question about mutations -- there's not much to report. Any time that DNA gets copied, there are errors. Not more, AFAIR, than a few per billion, but it's enough to permit differential reproductive success (aka selection) to take place.

Guest

Thanks a million guys.

I'm much clearer now on the process.

5uspect

() wrote:

These questions should hopefully give you an idea of where my haziness lies. Does Dawkin's Selfish Gene go into this sort of detail?

I'd appreciate if someone could point me in the right direction.

Thank you

Yes, the Selfish Gene goes thru the whole shebang and Dawkins does it again in the Blind Watchmaker but this book is designed more to convince the unwashed.

I see Easons In Limerick have a shelf load of new editions I'm sure you'll find a copy in your local one.