Monday, March 26, 2007

Reflectance Detectors (aka Eyeballs)

Color blindness may be more troublesome now than ever due to our reliance on computers and graphic images for conveying information. But, according to this article in the Boston Globe, Tenebraex Corp. has come up with a relatively simple solution. The company designed a computer program that allows users to interact with the colored areas in an image in a variety of ways. Here's a flash animation of the program.

On the other side of the spectrum, researchers may have located women that are able to perceive more than the normal range of colors. Normally humans are able to see well in three areas of the light spectrum (blue, green and red) using three types of cones (light-detecting structures in the eye).

Color detection genes reside on the X chromosome which is why color blindness is much more common in men. Men have only one X and therefore only one copy of each gene. Check out this great post over at damninteresting.com.

I've always wanted to be on the same wavelength as the birds and the bees and the flowers and the trees- all of them can communicate using ultraviolet signals. Birds have feathers that reflect in the ultraviolet range and receptors to receive those messages. Flowers also display UV-reflectance to lure insects (including bees) for pollination.

Monday, March 19, 2007

Two can play at donkeys.



A Distinction with a Difference

My lab recently got a sample of a mystery animal from another campus lab. Well, not completely mysterious. The sample was from the baby of a donkey. But they weren't sure if it was a hinny or another donkey. Hinnys are hybrid animals produced by breeding a female horse and a male donkey. Mules are the opposite of hinnys, their mothers are donkeys. Like many other hybrids, mules and hinnys are typically sterile because they have an odd number of chromosomes (see chart). Hinnys and donkeys can usually be distinguished by appearance but if the animal is too young they can be distinguished by counting their chromosomes. Donkeys have 62 chromosomes and hinnys (and mules) have 63.

Zedonkey

The liger is probably the most famous hybrid animal. But it also has an lesser known "opposite" called the tigon. People went crazy with zebras as well creating zorses, zonies, zetlands, zebrasses and zedonkys.

I don't know what this one is called though.

Mom
Dad
Offspring
# of chromosomes
Sterile?
Female Horse (Mare)
Male Donkey (Jack)
Mule
63
yes
Female Donkey (Jenny)
Male Horse (Stallion)
Hinny
63
yes
Female Horse (Mare)
Male Horse (Stallion)
Horse
64
no
Female Donkey (Jenny)
Male Donkey (Jack)
Donkey
62
no

Female Mule (Molly)

Male Horse (Stallion)
?
?
?
Female Hinny
Male Donkey (Jack)
?
?