| Andrew Cooke | Contents | Latest | RSS | Twitter | Previous | Next

C[omp]ute

Welcome to my blog, which was once a mailing list of the same name and is still generated by mail. Please reply via the "comment" links.

Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

Personal Projects

Lepl parser for Python.

Colorless Green.

Photography around Santiago.

SVG experiment.

Professional Portfolio

Calibration of seismometers.

Data access via web services.

Cache rewrite.

Extending OpenSSH.

Last 100 entries

NYT Has More Details; Obvious Question; Advertising Low Cost Routes?; Similar Analysis Here; My Current Take On Surveillance Scandal; Last.fm is Hiring; How I Am 2; The back-wards compatibility fallacy; Wiggle The Mouse To Pass The Test; Python Enums on Crack, Part II; Multiple Monitors with Linux; What Is Happening In Turkey; A Simpler Enum; John Fogerty on IAmA; And You May Well Ask...; Progress on a Better Enum; I'm a MACHIIIIIIIIIIIIIIINE; Those little tab things on the side of jet engines; Re: Python's sad, unimaginative Enum; Some explanation; Printing binary trees sideways; About "Python's sad, unimaginative Enum"; Atoms in python; Some good feedback here; Frustration Understood; I agree with you #nt; What would be imaginative?; Re: Enum; this is fucking useless; Enum; Python's sad, unimaginative Enum; Possible Fix; Work, Exhaustion, Vacation; VirtualBox with Centos 6.3 to 6.4, client; Matasano - Programming Lessons Learned; PDF to HTML; Alternate Substitution; Why RSA Works; Trigger; Dreaming of Death; Example: Tracing; Using Coroutines In Protocol Simulations; Python 3.3 Only; Pure Python SHA1 and MD4 Implementations; Ubuntu on VirtualBox; Starting TOR as a service on OpenSuse 12.3; 1001 Albums; Using fail2ban on OpenSuse 12.3; PPPoE on OpenSuse 12.3; Good Article on Unified Physics; It's Police (Carabineros); Linux Software for Listening to and Exploring Music; Android is Pretty Bad; Lucky Number; 3D Printing for Casting; Cover Art for MPDroid; Who'd a thought the French were so bigoted?; PS Input Signal; Small Problem with Roksan K2 Amp; Roksan K2 Amp + ATC SCM7 Speakers; Do What Makes Sense; Re: Arguing About Tests, Still; Arguing About Tests, Still; Images; Good Article on NY Drummers; Related Bug Report; Getting Python 3.3 and Virtualenv Working in OpenSuse 12.3; How I Am; Awesome video about digital audio; The Difference Between Dimensional and Normalized Databases; The rise of the new Chinese bogeyman; Updated Syntax; Very First Steps to C-ORM; The Ideal User Interface For Music Exploration; Can The Republicans Be Saved?; Rate Limiting Calls to EchoNest; Mods to Cache; Comparing UYKFG and UYKFD/E/F; Someone Else is Concerned; EchoNest-based Playlist Generator for MPD; Example Voting Results; A Heavyweight Python Cache; Identifying Artists with EchoNest; Notes on Pregalex / Pregabalina / Lyrica; The Neil Cowley Trio; Drake - Make for Data; A Reliable Python Web Service; Useful Python Date/Time Library?; Need to Sleep, But this is Good; Command Line Set Difference; Little Details...; Linux Command Line Tricks; AutoTools Tutorial; Hangman Tactics; A Tor Proxy Embedded In A Web Page; Tree (Nested Dicts) in Python; Sleeping at Parties; I Know Someone Who Hurts Other People; Light and Tea; Description of the LCS35 Time Capsule Crypto-Puzzle; Re: I can relate to that ...

© 2006-2013 Andrew Cooke (site) / post authors (content).

Evolution of Colour

From: andrew cooke <andrew@...>

Date: Sun, 11 Dec 2011 17:56:25 -0300

OK, so here's a possibly interesting question that just came up while talking
to Paulina: how did colour vision evolve?

You might answer: so that animals could see more detail.  But what would they
see?  Most natural things are either brown or green.  And the blue sky.  Is
that enough to motivate three colour vision?

"What about colourful flowers, or fruit, or birds?" you might ask.  But then
how did *they* evolve?  Because I would have thought that the standard
explanation there is that they are evolved to be attractive to colour vision.

So apart from green / brown / blue, we seem to have a chicken and egg
situation: bright plumage / fruit / flowers wouldn't evolve until there was
colour vision to detect them; but without them, why evolve colour vision?

Presumably things boot-strapped on green / brown / blue and then more
resolution / brighter colours co-evolved.  Which I guess works, but isn't as
cute a "just so" story as you might hope.

Or maybe there's some technical argument that says that green / brown / blue
requires three detectors (why not two?)...

Andrew

evolution of color vision

From: Stefan Wehner <stefan@...>

Date: Sun, 11 Dec 2011 19:31:26 -0500

I remember too, it has to do with the color of fruit and the different =
hues of green (and even red) which mark the younger and more nutritious =
leaves. A couple of years ago I read a book about evolution: Sean B. =
Carroll: The making of the fittest. It devotes a whole chapter on the =
issue and goes into the details of which molecules are responsible for =
which color, what are the genes that codify them and how these genes =
shifted between different animals. By the way, only the Old World apes =
have trichromatic color vision. American monkeys as well as rodents and =
other mammals only developed dichromatic vision. Birds and even fish can =
see colors and it seems that color vision was acquired early in =
evolution, then lost in many species and subsequently redeveloped. =
Pretty fascination topic and I can recommend the book.

Stefan=

Seeing red

From: Manuel Simoni <msimoni@...>

Date: Sun, 11 Dec 2011 22:07:47 +0100

From Wikipedia's http://en.wikipedia.org/wiki/Evolution_of_color_vision

"Ability to perceive red and orange hues allows tree-dwelling primates
to discern them from violet. This is particularly important for
primates in the detecton of red and orange fruit, as well as
nutrient-rich new foliage, in which the red and orange carotenoids
have not yet been masked by chlorophyll."

Comment on this post