davegodfrey: South Park Me. (Default)
As I've not updated this in ages, other than the automated Twitter-stuff, which I'm sure you're all sick of by now I thought I'd dig this out. It seemed like fun at the time, and as I don't do fanfic or "stuff in great detail" type things I'll get a day off here and there.

day 01 → your favourite song
day 02 → your favourite movie
day 03 → your favourite television program
day 04 → your favourite book
day 05 → your favourite quote
day 06 → whatever tickles your fancy
day 07 → a photo that makes you happy
day 08 → a photo that makes you angry/sad
day 09 → a photo you took
day 10 → a photo of you taken over ten years ago
day 11 → a photo of you taken recently
day 12 → whatever tickles your fancy
day 13 → a fictional book
day 14 → a non-fictional book
day 15 → a fanfic
day 16 → a song that makes you cry (or nearly)
day 17 → an art piece (painting, drawing, sculpture, etc.)
day 18 → whatever tickles your fancy
day 19 → a talent of yours
day 20 → a hobby of yours
day 21 → a recipe
day 22 → a website
day 23 → a YouTube video
day 24 → whatever tickles your fancy
day 25 → your day, in great detail
day 26 → your week, in great detail
day 27 → this month, in great detail
day 28 → this year, in great detail
day 29 → hopes, dreams and plans for the next 365 days
day 30 → whatever tickles your fancy
Ctrl+Enter to post

There are no guarantees of actually completing this, but we'll see how far I get...
davegodfrey: Hello Cthulhu! (Cthulhu!)
Rules: Once you've been tagged, you are supposed to write a note with 25 random things, facts, habits, or goals about you. If I can be arsed by the end of this there may be tagging.

1. My first "proper" gig was seeing Metallica at the Ministry of Sound when I was 18.
2. I am allergic to penicillin
3. I have never attempted to wear contact lenses
4. I cannot remember how long it has been since I have had a haircut.
5. I have never taken a driving test.
6. I was paid to photograph echinoids for six months.
7. I am fascinated by the history of science.
8. I always wanted to be a palaeontologist.
9. I have seen Slayer more often than any other (signed) band.
10. I have never read a work of "modern literary fiction" that I wasn't going to be examined on.
11. Despite being raised without any religious instruction I have Catholic Guilt.
12. I have virtually no short-term memory.
13. I have no tolerance for new-agey stuff- astrology, crystal healing, etc.
14. I have never owned a games console. Nor do I have any real interest in rectifying this.
15. I like sprouts.
16. I have had what would be classed as plastic surgery.
17. I have always loathed Cadbury's Creme Eggs. I don't have a particularly sweet tooth.
18. I have a completely irrational dislike of handling slugs. Snails do not affect me in the slightest. I think its because of the shell.
19. The only sporting prize I ever won was a five metre swimming badge.
20. I will spend 20 minutes trying to compose a two-line response to a blog post. And then not send it.
21. I get vertigo standing at the bottom of open-plan staircases, yet I had no qualms about going up the CN tower.
22. I am much shyer than people might think. 
23. I have absolutely no idea what most people who work in an office actually <i>do</i>.
24. David Godfrey "was not of woman born".
25. Tagging people takes far too bloody long so I won't bother
davegodfrey: South Park Me. (Default)
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What do you mean fossils don't count as technology?
davegodfrey: Flying Spaghetti Monster : Touched by his noodly appendage (FSM)
John Wilkins (at Evolving Thoughtshas a list of basic science concepts he thinks everyone should know.

The concept of "the gene" has attracted a fair bit of discussion, (I've only just noticed it but I haven't done a decent sciencey post for a while.)

Lots of different ideas.

Larry Moran doesn't like Dawkins' definitionHis own is "a DNA sequence that is transcribed to produce a functional product". He doesn't include control regions, or other untranslated bits, but does include the translated bits that aren't used to make the protein/RNA (not all DNA makes proteins folks).

PZ Myers uses  Griffiths, Lewontin Miller & Gelbart's book "Modern Genetic Analysis: Integrating Genes and Genomes" definition. "A gene is an operational region of the chromosomal DNA, part of which can be transcribed into a functional RNA at the correct time and place during development. Thus, the gene is composed of the transcribed region and adjacent regulatory regions."

Dr S.P. doesn't like this. She has "a problem with the words "chromosomal," "DNA," and I guess even, the phrase "the correct time and place during development." " Why? Well, cancer is triggered by genes being transcribed in the wrong time and place. Some genes are on nucleic acids that aren't DNA, and others on things that aren't chromosomes (and in HIV's case both). Her definition? "A gene is a heritable string of nucleotides that can be transcribed, creating a molecule with biological activity."

Dawkins (for those who haven't read the Selfish Gene [do so. now!]) says "A gene is defined as any portion of chromosomal material that potentially lasts for enough generations to serve as a unit of natural selection". While this means that Dawkins doesn't have to worry about the details of the gene its a rubbish definition if you actually want to look at the DNA/RNA you've got. Where does the gene start? Where does it end? Its at this point that you start refining it down and pinpoint specific locations, but for behavioural ecologists its often impossible to say how much of a behaiour is environmental, genetic or what combination of the two.

I think it all depends on who you're talking to. That and the fact that the word was invented in 1909 before we knew what DNA did. 

For palaeontologists and evolutionary biologists a gene is a chunk of genetic information with a phenotypic effect. The internal structure of Hox genes isn't particularly interesting to me, what is interesting is how many of them there are, where they are expressed and how they are shared across phyla. I would lump the regulatory region in with the rest of the gene as a mutation here affects the gene's expression (and I wouldn't describe the regulatory region as a gene in its own right).

A behavioural ecologist could make do with something approaching Dawkin's definition of a gene. By the time a gene's effcts have made it to the outside world it doesn't matter if the change that distinguishes it and an allele is in the intron (the transcribed region), the cistron (the coding region), the regulatory regions, or another untranscribed portion.

To someone looking more closely this glosses over a whole world of complexity, sections of DNA coding for more than one product, non-transcribed bits affecting transcribed bits, products made form apparantley unrelated sections of DNA.

For my part, (in his comment on Pharyngula) Peter Ellis's definiton of: "A gene is a unit of DNA which is transcribed, has a phenotypic effect when transcribed, and whose phenotypic effect is altered by mutation" is, I think, the best one for the interested (or disinterested) layperson to start with. It doesn't worry about the fact that an awful lot of DNA gets transcribed at various points and doesn't do much that and  If they then start to ask questions about how exactly these "gene" things work the detail comes in.

I know this means the control regions get excluded, but if its clear that thereare more things involved in a "gene" than just the gene itself then I don't think that matters. Maybe we need another word to argue about?

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davegodfrey: South Park Me. (Default)
The Evil Atheist Your Mother Warned You About

November 2013

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