Is This True

[Miss Wiggle]

was talking abouth the collosal squid with someone on another forum yesterday, he said this

"They can grow that big because of the relative lower gravity created by boyancy in water."

any truth in it?

 

[andywg]

Aquatic mammals can grow large as the water supports a lot of the weight. A whale's skeleton supports almost none of the weight from its body which is why they die if left out of the water too long as the organs will become distended and crushed.

As one travels further down into the water pressure on any air spaces increases at a rate of roughly 1 Bar per 10m, though this should have little effect on entirely aquatic organisms such as squid.

I think there are far more factors that would affect the size they grow to. After all, look at the size a number of the land dwelling dinosaurs reached, and that was without water to support them.

 

[Miss Wiggle]

thanks andy, I was hoping you'd reply!

so basically yes it will have had some impact on how the animals evolved so large, but animals as large could also evolve out of water depending on a number of other conditions so it's probably not the only or maybe not even one of the main reason's they get so large

 

[andywg]

To be honest, I think the other party has terms mixed up. I am digging up GCSE physics here, but the attractional gravitational force of an object involves squaring. So an object twice as far away from the object experiences only a quarter of the force.

In theory moving under sea level increases gravity, however water is around 800 times denser than air, so the body will have more support. I would say that environmental factors such as food supply and possibility of predation affect the size something gets to more than anything.

To grow that big there must be a fairyl large supply of food somewhere at some time to enable that size to be maintained. Generally the larger animals either eat large prey (think Great White) or eat huge quantities of small prey (think Blue Whale).

Looking at the Squid I would say they are not designed for the mass filtration of planktonic life, and I would be surprised to see enough plankotnic life at that depth to support such large creatures. This would then raise the question of what they are eating. I would assume they are eating other deep water creatures that are of a similar or slightly smaller size.

But then our understanding of the real depths of the oceans is so limited we have very litte idea of what really goes on down there.

 

[kniesh]

I'm not sure here but I would imagine part of the reason that this squid has evolved so large in some part to do with the area it lives. Antarctic species probably means it was required to grow so large to keep a sustainable body heat.

 

[Miss Wiggle]

To be honest, I think the other party has terms mixed up. I am digging up GCSE physics here, but the attractional gravitational force of an object involves squaring. So an object twice as far away from the object experiences only a quarter of the force.

hmmmmm and bearing in mind i was born blonde...... what??

But then our understanding of the real depths of the oceans is so limited we have very litte idea of what really goes on down there.

very very true!

I'm not sure here but I would imagine part of the reason that this squid has evolved so large in some part to do with the area it lives. Antarctic species probably means it was required to grow so large to keep a sustainable body heat.

good point


edit - buggered that up didn't i!

 

[kniesh]

To be honest, I think the other party has terms mixed up. I am digging up GCSE physics here, but the attractional gravitational force of an object involves squaring. So an object twice as far away from the object experiences only a quarter of the force.

In theory moving under sea level increases gravity, however water is around 800 times denser than air, so the body will have more support. I would say that environmental factors such as food supply and possibility of predation affect the size something gets to more than anything.

To grow that big there must be a fairyl large supply of food somewhere at some time to enable that size to be maintained. Generally the larger animals either eat large prey (think Great White) or eat huge quantities of small prey (think Blue Whale).

Looking at the Squid I would say they are not designed for the mass filtration of planktonic life, and I would be surprised to see enough plankotnic life at that depth to support such large creatures. This would then raise the question of what they are eating. I would assume they are eating other deep water creatures that are of a similar or slightly smaller size.

But then our understanding of the real depths of the oceans is so limited we have very litte idea of what really goes on down there.

Probably eat the same as Giant Squid which has been known to attack small whales.

 

[GoldfishAttentionSpan]

You know, in class we watched a video on deep sea creatures, and I can't remember any that were overly large. Then again, most of the creatures they talked about where vertebrates, but I do remember one octopus they said was the size of a beachball. I think they said why the fish tend to be small, but I can't remember why that was...