Cambridge Chat (previously New Cambridge Students Entry 2004)

woh

i can't keep up with your deep scientific discussions! i dropped biology after gcse!

"The coefficient of relatedness (r) between two individuals is defined as the percentage of genes that those two individuals share by common descent. That may seem a little complicated, but it is actually easier to calculate than to define. Consider the simplest example of calculating the coefficient of relatedness of a parent and its offspring in a diploid system. The offspring inherit 1/2 of their genome from a particular parent, so that they will have a coefficient of relatedness of 0.5. If you take this one generation further, the offspring's offspring (grandoffspring) will have 1/2 of the genome of its parent, and consequently 1/2*1/2=1/4 of its genome from its grandparent. Thus, a grandparent and grandoffspring have a coefficient of relatedness (r) of .25. In general r =.5n where n is the number of "generational links" (Campbell 1993)."

I realise it would vary. I was going through a vast array of big chunky textbooks on evolution, ecology (for the altruism idea and sacrificing yourself for a sibling's niche, etc) and general biology ones. I couldn't find anything relating to humans except a couple of comments alluding to the coefficient of relatedness being 0.5 between siblings. I think I'll look up a better definition of that coefficient!

I do think that it ought to be around 50% common source though, but that's rather meaningless

Just found this...

"The coefficient of relatedness (r) between two individuals is defined as the percentage of genes that those two individuals share by common descent. That may seem a little complicated, but it is actually easier to calculate than to define. Consider the simplest example of calculating the coefficient of relatedness of a parent and its offspring in a diploid system. The offspring inherit 1/2 of their genome from a particular parent, so that they will have a coefficient of relatedness of 0.5. If you take this one generation further, the offspring's offspring (grandoffspring) will have 1/2 of the genome of its parent, and consequently 1/2*1/2=1/4 of its genome from its grandparent. Thus, a grandparent and grandoffspring have a coefficient of relatedness (r) of .25. In general r =.5n where n is the number of "generational links" (Campbell 1993)."

That's very annoying, because Campbell was one of the textbooks I was looking through last night (albeit a 1999 reprint)!

i love campbell (if we mean the same one - Neil?) but the book does skate over things at some points i noticed.. hehe

He's the dude

I used to like go into the bath with it and stay there for like about 5 hours letting water out to get more hot water in and ending up like a prune because I was so addicted to it! Which version/reprint do you have?

There's that and Begon. They are the sort of things I read for fun... How sad am I?! I did read Sophie's World and The Elegant Universe over the past while as well, so I guess that's not so bad!

it isssssss............][ the 4th edition apparently, i got it off ebay. i particularly like the mini coloured rabbits, flowers etc in the section on genetic crosses...lol

its a bit heavy for me to read in the bath however. but i know what you mean about the water getting cold etc.. once i start reading something i do find it hard to stop unless its incredibly boring so i am often really tired for school because i was up reading until 3..lol..

Huh! No rabbits in 5th ed! It just has boring old quarters, mice and flowers!

Make yourself a lecturn (is that what you call them?)... Put it over the bath and you can read Campbell and other large heavy hardbacks without them sinking you!

I know the feeling.. With me, I seldom start reading but when I do, you can't get the book off me until I finish it or fall asleep!

If the link has the word slash in it I'm staying clear!

ooh i love sophie's world. its so surreal and really interesting. have you read anything else of jostein gaarder's?

Didn't know he wrote other stuff.. Thought it was a one-hit wonder thing Let me know stuff and I'll check it out when I get back

yeah he's written loads of other novels (aand some children's books): Jostein Gaarder (amazon)

none as good as Sophie's World admittedly, but the ones i've read have still been interesting, thought provoking and extremely surreal.

i hope there's a sailing club! i'd join that! oh and any walking/hiking clubs!

but not rowing 10 days a week or whatever

rosie