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MatC
286493.  Thu Feb 28, 2008 8:43 am Reply with quote

Thanks, Flash.

Did we ever use the goldfish memory myth? Buggered if I can remember ...

 
Flash
286498.  Thu Feb 28, 2008 8:46 am Reply with quote

No, I don't think so.

 
Flash
290600.  Wed Mar 05, 2008 4:56 am Reply with quote

From a new poster in the outer darkness:
Quote:
Hiccups happen when your brain stem forgets you don't have gills

From WIRED Science:

"One of the most perplexing and vexing of mild human afflictions is the hiccup, or as it is medically known, the singultus. Through the years, many (ineffective) remedies have been suggested, from holding your breath to scaring yourself. But a larger question remained unresolved: why do humans have these involuntary spasms of the diaphragm, which produce uncontrollable funny noises at irregular and inconvenient times?

Now, University of Chicago anatomist, Neil Shubin, has provided the world with an explanation in his book Your Inner Fish. As described in the Guardian:
Quote:
Hiccups are triggered by electric signals generated in the brain stem. Amphibian brain stems emit similar signals, which control the regular motion of their gills. Our brain stems, inherited from amphibian ancestors, still spurt out odd signals producing hiccups that are, according to Shubin, essentially the same phenomenon as gill breathing.


This is atavism, or evolutionary throwback activity, at work. Luckily, you do eventually stop trying to breathe through your gills when it dawns on your brain that you are actually a modern human, not a prehistoric fish."

http://blog.wired.com/wiredscience/2008/02/evolution-expla.html
post 290531

Is this respectable science or a bit fishy? I have no idea, but it might be one for the notes.

 
dr.bob
290617.  Wed Mar 05, 2008 5:17 am Reply with quote

I don't know enough about anatomy to be sure, but the fact that this claim is made in a book, rather than a peer reviewed journal, makes me think that you should be rather careful about presenting the information.

If it's in a note, probably best to make it clear this is what one person thinks, rather than presenting it as factual.

 
dr.bob
290629.  Wed Mar 05, 2008 5:38 am Reply with quote

More detail in this article, adapted from the book.

Apparently "Cats can be stimulated to hiccup by sending an electrical impulse to a small patch of tissue in their brain stem." Well, I never knew that.

The actual meat of the problem, though, smells a bit odd to me. He seems to explain the same problem twice.

He begins by saying that the part of the brain that controls breathing is the same that controls gill breathing in fish. The gills of a fish tend to be near to the brain stem, but the diaphragm of a mammal is much further away. Thanks to evolution, though, the nerves that travel to the diaphragm to control breathing exit the brain stem up near the head, where the gills should be, and then travel a long way to the diaphragm, thus rendering them more prone to interference or irritation than if they did the sensible thing and exited the spinal cord much closer to the site of the diaphragm. So far, so vague and woolly.

However, the then goes on to say that the "hic" sound is caused by the glottis slamming shut, which is the same kind of behaviour seen in tadpoles when they're gill breathing. Tadpoles, possessing both lungs and gills, have a mechanism whereby they breathe in and immediately shut the glottis so that the water they breathe will be directed over their gills and not enter their lungs. He claims (but gives no references to back it up) that this same "pattern generator" is present in humans and causes hiccups.

Firstly, if that's the case, where does the whole "badly designed nerve pathway" come into it? Secondly, I was always told that the glottis slammed shut simply because such a sudden intake of breath pushed it shut, just like a door slamming closed in a strong wind. If that's correct, then the tadpole "pattern generator" is not required to explain the phenomenon. If that's wrong, and the glottis is being deliberately closed, then I wish he'd provided some evidence to show that this is the case.

I find his description of our prevalence for groinal hernias being related to evolution from fish designs to be more convincing, however, and probably more suited to smutty humour :)

 
MatC
294580.  Wed Mar 12, 2008 8:17 am Reply with quote

The first “working man” to become a government minister in Britain was John Burns, elected MP for Battersea in 1892.

He became famous as one of the leaders of the great dock strike of 1889 (an extraordinary and world-changing event, with many fascinating details; not least that, just as it seemed the dockers had been starved back to work, the Australian trades unions sent them an emergency donation of £25,000).

For present purposes, however: Burns (known to the press as “the man with the red flag”) was a whiz at getting publicity for his causes. He had the dockers march through the City holding up “stinking onions, old fish heads and rotting meat on poles, to demonstrate against the appalling food that they were forced to eat because of their poverty.”

S: Morning Star, 16 Feb 08.

(PS: the word “docker” is unknown to Windows’ spellchecker ...)

 
MatC
295561.  Thu Mar 13, 2008 3:58 pm Reply with quote

At a single spawning, a female cod lays 4-6 million eggs - all “but a handful” are eaten by other sea creatures.
- http://www.stemnet.nf.ca/cod/history4.htm

 
MatC
295944.  Fri Mar 14, 2008 8:08 am Reply with quote

Dan Quayle (ahh, those were the good old days!) is reported as being the author of this wonderfully mangled proverb:

Quote:
FLEXING HIS RHETORICAL MUSCLES BEFORE THE VICE-PRESIdential debate, DAN QUAYLE explained what he called the essence of the Republican campaign. "If you give a person a fish," he said, "they'll fish for a day. But if you train a person to fish, they'll fish for a lifetime."


S: http://www.time.com/time/magazine/article/0,9171,976867,00.html?promoid=googlep

 
Flash
295966.  Fri Mar 14, 2008 8:23 am Reply with quote

It's only missing one word, though: "they'll have fish for a day".

Curiously enough he said something which relates to another discussion we're having:
Quote:
"Mars is essentially in the same orbit . . . Mars is somewhat the same distance from the Sun, which is very important. We have seen pictures where there are canals, we believe, and water. If there is water, that means there is oxygen. If oxygen, that means we can breathe."

 
eggshaped
295978.  Fri Mar 14, 2008 8:36 am Reply with quote

Mat wrote:
Quote:
female cod lays 4-6 million eggs - all “but a handful” are eaten by other sea creatures.


But a handful could be a hell of a lot when you're considering eggs of 1-2mm diameter.

 
MatC
295987.  Fri Mar 14, 2008 8:43 am Reply with quote

True! Most sources say "half a dozen," but I couldn't find a good source that said that.

 
dr.bob
296002.  Fri Mar 14, 2008 9:03 am Reply with quote

Flash wrote:
Curiously enough he said something which relates to another discussion we're having:
Quote:
"Mars is essentially in the same orbit . . . Mars is somewhat the same distance from the Sun, which is very important. We have seen pictures where there are canals, we believe, and water. If there is water, that means there is oxygen. If oxygen, that means we can breathe."


Well, looks like he might have been right about the water:

http://www.nasa.gov/mission_pages/mars/news/mgs-20061206.html

Though he obviously wasn't paying attention during his orbital mechanics lectures.

 
Frederick The Monk
297751.  Tue Mar 18, 2008 5:05 am Reply with quote

Q: Where do killifish live?



A: In Trees.

Quote:
Something fishy is happening in the mangrove forests of the western Atlantic. A fish is living in the trees.

The mangrove killifish (Kryptolebias marmoratus) is a tiny fish that lives in ephemeral pools of water around the roots of mangroves. When these dry up the 100-milligram fish can survive for months in moist spots on land. Being stranded high and dry makes it hard to find a mate, but fortunately the killifish doesn't need a partner to reproduce. It is the only known hermaphrodite vertebrate that is self-fertilising.

Now biologists wading through muddy mangrove swamps in Belize and Florida have discovered another exceptional adaptation. Near dried-up pools, they found hundreds of killifish lined up end to end, like peas in a pod, inside the tracks carved out by insects in rotting logs. "They really don't meet standard behavioural criteria for fish," says Scott Taylor of the Brevard County Environmentally Endangered Lands Program in Florida.


New Scientist: The swamp fish that loves to live in trees, 19 October 2007, Elie Dolgin, Magazine issue 2626

 
Flash
297753.  Tue Mar 18, 2008 5:07 am Reply with quote

Very nice.

 
eggshaped
309045.  Wed Apr 02, 2008 8:33 am Reply with quote

Fishing:

Scientists are devoloping a species of bass that will catch itself.

They will swim into a net when they hear a tone that signals feeding time. The hope is that they could be set out into the wild and then swim into an underwater cage to be harvested when they hear the signal.

I wonder if it could be used to coax killifish out of trees?

http://www.guardian.co.uk/world/feedarticle/7413256

 

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