19 April 2012

Pregnant male seahorses


Let's finish with two photos of seahorses.  The top image (©Lazaro Ruda, via animals, animals, animals) shows a male seahorse giving birth.
In sea horses, the male become pregnant.  Their mating involves the female inserting her oviduct into the male’s brooding pouch.  She does this several times for short intervals to avoid exhaustion... The eggs are fertilized and hatch in the male’s pouch.  The size of the sea horse brood varies within sea horse species.  Some species’ broods are as large as 200 while others are as small as 8.

The males are pregnant for several weeks before giving birth to their brood .  When they prepare to give birth, the pouch extends to an almost spherical shape.  The male also undergoes muscular contortions - a forward and a backward bend - that last for about ten minutes.  Then in an explosive action the brood leaves the pouch.
The lower seahorse (from Quarks to Quasars, via A London Salmagundi) is also pregnant, but the emphasis is on the remarkable coloration and configuation of the creature.

8 comments:

  1. In that case, what makes the male seahorse the male gender?

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    1. Even women who lack the ability to give birth are of the female gender, no? (Prob'ly the same with the sea horses.) Genetically speaking. I imagine the males of the species still make sperm, the females produce eggs...all the usual trappings.

      That bottom picture is amazing. I love it.

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    2. Interesting choice of the phrase "the usual trappings".

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    3. Scientifically, in species with 2 sex chromosomes & 2 genders (some insects, specifically butterflies, have more than 2 genders) I think male gender is defined as the gender that has both types of sex chromosomes. So in mammals, including humans, the sex chromosomes are X and Y. Females are the ones with XX and males are the ones with XY. So male seahorses must be the ones with the ones with XY (I believe seahorses have X and Y like most animals).

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    4. Rosa, there are women who have a condition called Androgen Insensitivity Syndrome (AIS) who are genetically male (XY), but because their bodies are resistant to male hormones (androgens) they develop physically as females. They are completely physically, mentally, and psychologically female, but genetically male. They only female organ AIS women lack is a uterus and therefore they do not menstruate. Their ovaries are actually testicles. Many AIS women are utterly shocked when their condition is discovered; badly enough to require psychological counseling to accept their condition.

      Some people may jump to the conclusion that women with AIS should have a masculine appearance, but according to reports I read about the subject many AIS women tend to be very attractive. It is interesting reading.

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    5. Having seen a few women with AIS, I don't think I'd go so far as saying they're especially attractive. They look like women. Female is the 'default' for mammals, which is why they look as female as they do. They tend to be flat-chested, for obvious reasons, which either increases or decreases their attractiveness depending on your taste. The major bonus they get is a lack of the androgen-related appearance problems that many women deal with, including 'beard-line' acne and excessive facial hair.

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  2. Relevant:

    http://i.imgur.com/6Zmhv.gif

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  3. I'm sorry, but looking at the picture of the pygmy seahorse (H. bargibanti), all I could think of was, "Somebody pull my finger. For the Grace of God, somebody PLEASE pull my finger–!"

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