I am somewhat fascinated with the coelacanth fish. This family of fish
is a true survivor: It has survived for something like 360 million years
and has withstood basically everything nature has thrown at it, including
several ice ages and at least three mass extinction events (including the
Permian-Triassic extinction event which killed off about 96% of all marine
species of the time). It's one of the oldest families of animals with living
specimens today. Where basically everything else was killed by natural
disasters and mass extinction events, the coelacanth was unscathed.

  Then enter the most powerful natural disaster of them all: Humans.

  Thanks to humans the coecalanth is critically endangered and bordering
extinction. There are some species of coecalanth that have an estimated
less than 500 specimens alive, and dropping.

  Forget about mass extinction events, meteors smashing the Earth, ice
ages and other massive natural disasters. Leave it to humans to kill off
even the toughest of survivors.

  It's sad, really. Maybe the only consolation is that we will eventually
kill ourselves in the same way we are killing other animals, so after we
go extinct maybe other animals will once again have the chance to survive
the milder natural disasters such as ginormous meteorite impacts and other
astronomical events.

-- 
                                                          - Warp

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>  Then enter the most powerful natural disaster of them all: Humans.
>
>  Thanks to humans the coecalanth is critically endangered

Why do you think it is because of humans?  Populations of species go up and 
down pretty violently even without human involvement:

http://www.geo.arizona.edu/Antevs/nats104/00lect21lynxhare.gif

Does a similar graph for coecalanth exist?

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On 30-4-2009 16:37, scott wrote:
>>  Then enter the most powerful natural disaster of them all: Humans.
>>
>>  Thanks to humans the coecalanth is critically endangered
> 
> Why do you think it is because of humans?

An educated guess?

>  Populations of species go up 
> and down pretty violently even without human involvement:
> 
> http://www.geo.arizona.edu/Antevs/nats104/00lect21lynxhare.gif

Such large fluctuations can happen if there is just (effectively) one 
food source that determines survival of the hunter (or vice versa). If 
there are many independent prey animals the curves do not fluctuate as much.

> Does a similar graph for coecalanth exist?

I don't know exactly what the coelacanth eats of what eats it but I 
guess that is not very likely.

A possibly more relevant criticism might be that for a species where we 
don't really know in what habitat it lives it is very hard to estimate 
how many there are and if the number are declining. BTW I can not find 
an estimate for the current population with a superficial google search.

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scott <sco### [at] scottcom> wrote:
> Why do you think it is because of humans?

  Hundreds of species have been confirmed to have gone extint in the
past 100 years. Because only the most prominent species are noticed to
go extint, the true amount of extint species in the last 100 years is
estimated to be in the tens of thousands. This speed of mass extinction
is completely unprecedent (even the dinosaurs were not extinct even
nearly that fast). The amount of critically endangered species is
probably even larger. Also plants are going extint at an unprecedent rate.

  This phenomenon even has a name: The Holocene extinction event.

  Most of these extinctions have been directly attributed to human
intervention, such as destroying natural habitats, hunting and pollution.
It's not a coincidence that this mass extinction is happening at the same
time as the industrial revolution.

  Could the population loss of coelacanths happening right now be caused
by completely unrelated phenomena and its timing a complete coincidence?
Maybe. Rather big of a coincidence, though.

-- 
                                                          - Warp

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"Warp" <war### [at] tagpovrayorg> wrote in message
news:49f9c66b@news.povray.org...

>   Could the population loss of coelacanths happening right now be caused
> by completely unrelated phenomena and its timing a complete coincidence?
> Maybe. Rather big of a coincidence, though.

Why?

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>  Could the population loss of coelacanths happening right now be caused
> by completely unrelated phenomena and its timing a complete coincidence?
> Maybe. Rather big of a coincidence, though.
>
> -- 
>                                                          - Warp
Not really. I wouldn't be surprised though if we found that the coelacanth 
has been in danger for centuries or even thousands of years. They have never 
been known to be common, not during recorded history. If people are 
responsible for their current status, I can't imagine how it happened. If 
they were over-fished we would probably know about it. I don't think we have 
deprived them of a habitat- not yet. Their food supply has always, and still 
is, plentiful. It may sound like a dumb question, but, in what way has 
mankind contributed to the dissapperance of the coelacanth?

-- 

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Halbert wrote:

> It may sound like a dumb question, but, in what way has 
> mankind contributed to the dissapperance of the coelacanth?

For a moment there, I thought you were called Halibut.

That would be kinda fishy though...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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>
> For a moment there, I thought you were called Halibut.
>
> That would be kinda fishy though...
>

I kind of like the idea.


"I wonder where that fish did go? A fish, a fish, a fishy, oh!"

-- 

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Halbert <hal### [at] gmailcom> wrote:
> Not really. I wouldn't be surprised though if we found that the coelacanth 
> has been in danger for centuries or even thousands of years. They have never 
> been known to be common, not during recorded history.

  They were rather known in the Comoros by local fishermen because they
would occasionally get one in their net, so it's not like it has been a
completely unknown fish in recent history. Nowadays Comorians are trying
to preserve the coecalanths by returning them to the sea when they catch
one by mistake, because of their endangered status.

> If people are 
> responsible for their current status, I can't imagine how it happened. If 
> they were over-fished we would probably know about it. I don't think we have 
> deprived them of a habitat- not yet. Their food supply has always, and still 
> is, plentiful. It may sound like a dumb question, but, in what way has 
> mankind contributed to the dissapperance of the coelacanth?

  Large-scale commercial fishing has shifted from continental shelves to
their slopes, endangering many deep-sea fish species (because deep sea fish
reproduce very slowly).

-- 
                                                          - Warp

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No prob.  Pigs will avenge them all. ;)

-- 
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