How Male Seahorses Evolved to Give Birth

Male pregnant seahorses give birth to around a thousand babies. Seahorses come from the family Syngnathidae, which also includes seadragons and pipefish. They're the only animals in which the males get pregnant. After females transfer eggs, the males then fertilise them. But why do male seahorses give birth? And how did this way of reproduction evolve?

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Credits:

References:
Whittington CM & Friesen CR. The evolution and physiology of male pregnancy in syngnathid fishes. Biol Rev Camb Philos Soc 2020;95:1252–1272.
Roth O, et al. Evolution of male pregnancy associated with remodeling of canonical vertebrate immunity in seahorses and pipefishes. Proc Natl Acad Sci U S A 2020;117:9431–9439.
Wilson AB, et al. Male pregnancy in seahorses and pipefishes (family Syngnathidae): rapid diversification of paternal brood pouch morphology inferred from a molecular phylogeny. J Hered 2001;92:159–166.

#wildlife #nature #seahorse

[frankenscience]

Please like, comment and subscribe if you enjoy the video!

[daydreaming]

The seahorse looked like he were sneezing his kids out 😂 cute

[tu]

letting a comment for yt for one of the most underrated science channels, amazing quality content!

[gonzalogutierrez]

"... some eggs can be lost... "
I know almost nothing about seahorses (prior to watching this video), but that looked like a lot of eggs lol

Also, quality is incredible as always

[W-me]

You literally deserve more subscribers!

Your videos are pure excellence.

[ribxxns]

Humans: my wife is giving birth!!
Seahorses: My husbands giving birth!!!

[DefektiveEnvy]

You answer all the niche biology questions I have! Best channel, new favorite

[abstracter]

What an excellent well researched video, thank you

[simonbuchner]

Hello! Very glad to have found this top quality channel but you should change your voice audio processing.

For example the s-sounds are very sharp so maybe eq that out a little bit

[weentertain]

I don't know why I'm watching this, but I love it. Thanks for the information I just learned somethings.

[JillyBean_]

Seriously, this video is so professional. Because your subscriber count is so low (I have no idea how!) I thought maybe you stole a video from National Geographic or something! I promise I really mean that. Not just trying to stroke your ego!

[hop]

Just one video and instant subscribe. This video is short yet complete, easy to understand yet full of detailed information, helped me to visualize the evolution of seahorses and its relation to the relatives.

[tonyyero]

Male seahorses are unique among animals in that they get pregnant and give birth to their young. During courtship, female seahorses use a special ovipositor to inject their unfertilized eggs into the male's brood pouch, which is located on his tail. So YES, scientifically he is fertilizing her eggs and expelling them live!! THAT IS GIVING BIRTH. She carries the eggs...that simple.

[madmonkee]

I've always been fascinated by seahorses, pipefish, and seadragons.
A little trivia for you: in Baltimore, in the 50s and 60s (and maybe longer) seahorses were a secret symbol for lesbians (because it's the males that give birth).
There's something you won't see in a John Waters movie.

[emawerna]

Some fish, like the Platy fish we have in our home aquarium, give birth to live young. This is the female giving birth to live young. Live bearers like Platys have a reproductive advantage in a relatively crowded environment with other species (like a fish tank with other species of fish in it). The fry pop out of the mother and can swim to safety.

However, one gender is expending the energy. The female has to expend energy avoiding the males who want to mate all of the time. The solution in the home aquarium is to up the number of females for every male so that he is chasing around a lot of girls rather than just one. Wild female platys and other similar live bearer females in natural environments don't get such relief. So, female Platys have to expend energy: 1) avoiding males, 2) producing eggs, and 3) retaining those eggs in their bodies until the fry hatch. The females "blow up" when they are pregnant. They are less streamline, making it cost more energy for them to swim. Energy-wise, all the males have to do is find the females and mate with them. Instead of him searching the gravel or hiding spots for eggs to fertilize like with other fish species, he knows where the eggs he wants are. Hence, he chases the females relentlessly, putting more pressure on the females.

He has excess energy. She is struggling to swim well enough so that she can find enough food in her expanding pregnant body. Any energy intensive task she can give to him instead (like egg guarding or even male pregnancy) is going to mean more energy overall goes into producing offspring. With shared responsibilities, you are harnessing both male and female energy instead of only female energy.

So, Mrs. Seahorse gets to go eat and fill her body with eggs again before her previous brood in even born. As a result, there are more Seahorses in the world.

[paulinehalkyard]

What a brilliant video this was very interesting well done 😍😍😍😍

[iraeis]

got recommended this after watching the suicidal salmons video. You deserve to get blessed by the algo

[footfault]

From its appearance more like a reptile to unparalleled reproductive behavior, seahorse is missing nothing for wonder & awe.
Very illustrative as usual featuring the latest update in.
Grades of paternal care are shown leading up to the most complex one. Yet, evolutionary transition does not look as smooth or straightforward as presented here. Some steps more should be taken to the complex level of male reproductive system. That's the impression from this superb footage. Thank you very much! Next!

[tonyyero]

Male seahorses are unique among animals in that they get pregnant and give birth to their young. During courtship, female seahorses use a special ovipositor to inject their unfertilized eggs into the male's brood pouch, which is located on his tail. So yes, scientifically he IS giving birth as well as fertilizing them.

[Tereselynn]

This is amazing! Aren't they precious? Awe!