Science Fiction
Dictionary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
 |
This Species Has Seven Sexes
The single-celled organism Tetrahymena thermophila has seven sexes, not just two, which you would think would improve your odds tremendously.
(Young healthy VII WLTM I, II, III, IV, V, VI for conjugation
Image: Volker Steger/E. Cole/SPL)
Tetrahymena thermophila is a single cell covered with a coat of hairs called cilia. The cilia wave back and forth, powering it through the water.Its seven sexes are rather prosaically named I, II, III, IV, V, VI and VII. An individual of a given sex can mate with individuals of any except its own, so there are 21 possible orientations.
In most animals, what sex you are is straightforward. A human with two X chromosomes is female, while someone with an X and a Y is male...
Not so for Tetrahymena. Its sex is controlled by a gene called mat, but it is not as simple as one version of the gene encoding one sex. Instead, each allele of the gene sets out a series of probabilities. For instance, an individual born with the mat2 allele has zero chance of being type I, a 0.15 chance of being type II, a 0.09 chance of being type II, and so on.
There are at least 14 of these alleles, each offering a different set of probabilities...
Although not a prediction, sf writers often explore unusual, well, circumstances. In his sardonic 1949 story Venus and the Seven Sexes, writer William Tenn tells us about a rather complicated arrangement - the seven sexes of the Plookh.
"...I am a representative of the seventh sex - nzred.""A nzred, huh? What do you do?"
"I coordinate... You see, a mlenb is primarily interested in winning the affections of a likely strob and finding a tkan whom he can love. A tkan merely courts a mlenb and is attracted to a good guur. I am responsible for getting a complete chain of these individuals in operation, a chain of compatibility where perfect amity runs in a complete circle - a chain which will produce offspring of maximum variability. Then, after the matrimonial convention, when the chain is established, each sex begins to secrete in its original germ with the full forty-nine chromosomes. A busy time for the nzredd!
"The nzred... fits himself in at any point in the chain which the exigencies of the situation seem to demand. He may receive the sextuple supergamete from the tkan and transmit the original single gamete to the guur, he may be between the flin and blap, the blap and srob, whatever is required."
Via NewScientist.
Scroll down for more stories in the same category. (Story submitted 3/16/2011)
Follow this kind of news @Technovelgy.| Email | RSS | Blog It | Stumble | del.icio.us | Digg | Reddit |
Would
you like to contribute a story tip?
It's easy:
Get the URL of the story, and the related sf author, and add
it here.
Comment/Join discussion ( 3 )
Related News Stories - (" Biology ")
Lunar Biorepository Proposed For Cryo-Preservation Of Earth Species
'...there was no one alive who had ever seen them. But they existed in the Life Bank.' - John Varley, 1977.
Let's Make Slaver Sunflowers! Engineering Plants To Reflect Light
'The mirror-blossom was a terrible weapon.' - Larry Niven, 1965.
Machete-Wielding Philodendron Isn't Going To Take It Anymore
'The tree ended its wild larruping, stood like a dreaming giant liable to wake into frenzy at any moment.' - Eric Frank Russell, 1943.
Tsunami Forecasts Improved By Ionosphere Signals
'Swifter than any tide could ebb, the water was receding from the shore.'
Technovelgy (that's tech-novel-gee!) is devoted to the creative science inventions and ideas of sf authors. Look for the Invention Category that interests you, the Glossary, the Invention Timeline, or see what's New.
Science Fiction
Timeline
1600-1899
1900-1939
1940's 1950's
1960's 1970's
1980's 1990's
2000's 2010's
Current News
California Fireman Arrested For Starting Fires
'Fire is bright and fire is clean.'
Robots Need A Better Sense Of Touch
'First, it rubbed my arms...'
MouthPad Supports Head And Tongue Tracking
'The operation that had transformed half his body... had located the control switchboard in his teeth.'
REALLY Remote Control Excavators
'It takes over a second for the signal to get to the Moon...'
Disney Helping Robots Dance
Dance, Robots, Dance.
Kolors Virtual-Try-On Predicted, And TRIED, By Harry Harrison
'Bill blinked at his own face under the plumed helmet...'
Detecting Drones In Ukraine With Candy (Sukork)
'...a robot detector circuit closed, activating a bell."
Nevada Will Use AI To Decide Worker Benefits
'They had screwed up and been blacklisted by Manna.'
Tether Cryptocurrency Flow Rate US$190Bn Per Day
'Alex did not find it surprising that people... were electronically minting their own cash.'
First Trips To Mars Announced By Elon Musk
'I had determined that my first attempt should be a visit to Mars.'
WaPOCHI Micro-Mobility Robot Follows Like A Pet With Your Bags
To follow the user like a pet while carrying their cargo!
Ultra-Realistic Robotic Arowana Robo-Fish
'Deveet unhooked his catch and laid it on the bank beside him. It was a metal fish.'
GITAI R1 Lunar Rover Like NASA Robonaut Centaur
'...waldoes in the screen followed in exact, simultaneous parallelism.'
Meshworm Soft Robot, With Peristaltic Crawling, Is Getting Better
'Seen close it was not completely flexible, but made instead of pivoted and smoothly finished segments.'
Mushroom 'Robot' Is Just A Start
'Some unknown race ... decided to help them out.'
Tesla Electric 'Giga Train' Operational In Germany
'...the cars are wedge-shaped at both ends.'
