Why have there never been really huge animals?

Question

I know that elephants are huge, but there has never been an animal 35 miles long and 18 miles wide. Why? I think it has something to do with the size and weight of the earth, thus affecting gravity. Am I right?

Answer 1

Well there are organisms that are acces in size. One was recently discovered that was a interconnected field of mold I believe that was several acres in its toatal area. I know this is not a thinking type organism, but it is alive and interconnected. There are physiological limits as to how big a living, breathing animal with locomotion is however. One limit is that neurological impulses travel along nerves at a rate of about 256 feet a second. Therefore, movements that seem to be directed by the creatures mind would ultimately not be effective, if they were to require direction from a brain contained in the creature's head. Even human movements away from a hot stove i.e. are not brain directed movements, as they would be too slow, even in a human. These movements go to the spinal cord and immediately go back to the hand in a "knee-jerk" kind of response ripping the hand away from the heat source usually in time. Other weight and gravity related situations come into play as well. The blue whale, at 100 tons, is the largest creature ever to have inhabited the earth, even larger then any dinosaurs. However, beach one on the sand and it will die even though it is an air breathing mammal, because out side of the water it can not support its weight and eventually it can not breath and dies of suffication, although it is not a fish with gills. These principles seems to be universal and exobiologists who study life forms that may inhabit worlds even outside our solar system use these principles to come up with some bizzare possibilities, but which still manage to follow the physical and biological imperitives that would need to be at least part of the evolutionary aspects of inhabitants of other worlds universally.

Answer 2

Yes - you are right to a degree - but it is more gravity affecting the size and weight of the animal itself. Gravity is the main reason why there is nothing larger than an elephant. There can only be so much weight pressing on your life-sustaining organs and affecting blood flow. In fact, many have speculated that it was a shift in the earth that affected gravity which may have led to the dinosaurs' demise. Imagine a brontosaurus' neck suddenly not being able to lift/support its head!

Answer 3

There are dinosaurs which are the biggest animals so far in our evolutionary history.

Animals that are huge in modern time is Elephants, Whales such as Blue Whales are the biggest.

The environment just cannot support such large animals like 35 miles long. I don't think this would ever happen!

Yes I like other answers such as the "heart" cannot be big enough to support pumping blood that far....if such animal exist, i would imagine it must be pretty "DARN" slow! or would not be able to move very well at all! And it would be tired easily and most of the time.

Thus, natural selection would not select this type of trait. This trait would eventually become eliminated or extinct if it ever exist. Such "Huge" trait is inefficient and such a waste product for/of natural selection.

Answer 4

Yes there have been bigger that elephants animals in this planet. Actually many species of whales and squids are bigger that elephants. Your question about the non-existence of 38 by 15 miles size specimens have to do with environment and just plain physics. You see the type of bone density and structure required for such an animal would make it so heavy that most likely will sink on the ground. Secondly the amount of calories required to sustain such animal wouldn't be available. For that size my choice would be some sort of marine earth worm or some sort of aquatic animal where water can provide buoyancy. As for the amount of calories required to be kept alive I have no clue!

Answer 5

Gravity can hold an animal that's 35 miles long and 18 miles wide.

Answer 6

I think it's more along the lines of natural selection. An animal that big would require an immense amount of food. Thousands of tons... the entire earth would be eaten out of house and home. I think that if an animal gets too big, natural selection would cause them to starve.

And to respond to the insensitive people above, I believe the question was about an animal 35 MILES long. Dinosaurs are big, but we aren't talking just about big animals.

To those of you saying its a stupid question. I think it's a valid thing to ask. We have microscopic animals... why not huge ones?

He who calls another a name has run out of valid points to make and should stay out of the discussion.

To Kristal R: Um... isn't a blue whale bigger than an elephant? :D

Answer 7

an animal thta big might not be able to find enough food, or a big enough food source for its species to last very long, also it probably would be tooo big to develope any kind of a workable skelelton

of course if no one ever found a brontasaurous skeleton i might say the same thing about an animal the size of a brontasaurous... here's a discovery special that has big animals after the dinosaurs
http://en.wikipedia.org/wiki/Walking_With_Prehistoric_Beasts

p.s. is it me or does this guys answer make him sound like an A*sshole

cowboydoc said: {[[ Stop and think, what would it eat, where would it eat. An animal grows accordingly to it's environment. That's why so many of the earlier animals like the Sloth bear, the huge cave bear, the Sabre tooth cat, the huge red deer, etc, they had the world to live in. Today wild animals live in a closed environment. However you think about it, it's closed, they cannot roam where they want anymore. They cannot eat what they want anymore. Got it. }]

Answer 8

I think you might be onto something there, keep doing your research and coming up with helpful equations which will direct you toward the truth. Uh, there's got to be an explaination for why we've never seen a 35 mile long anteater on this planet before.

Gosh! What would you do in that situation!?

Answer 9

What about dinosaurs, they were supposed to be big. Think of it from a practical standpoint. How much food would a 35 mile long animal need? And where on earth would it live? It wouldn't. It would just die because it could not sustain itself. God was smarter than that when he created earth....

Answer 10

There have been huge animals in the earth, they are called mega fauna. True, they were never as big as the dimensions you posed, but they were in fact much larger than the largest presently existing animals.

For one thing the larger an animal is the more energy, or food it needs. Often times these animals ate their prey or land to a depleted state. Food can be scarce for animals and large beasts, are rarely scavengers. Without a constant and reliable food supply some these animals di.e.d off from over eating.

Humans, would be my second attribution to the extinction of the mega fauna. Large animals are threatening when we can not domesticate or break them in for our purposes. Many large beasts weren't as fast as small creatures so where large and slow targets for humans to kill off. ie the dodo bird.

Change in ecology, weather patterns, human domination and specialization have been the main culprits for many exquisite species extinction.