How does a moose get so large eating only plants?

[ledboots]

Interesting article.


Weird Animal Question of the Week: How Do Moose Get So Big Eating Plants?

"Food Chain Dynamics

Matthew Lewis, senior program officer for African species conservation at WWF, says it all comes down to "trophic levels," or where an animal sits in the food chain. The higher up you go, the more energy is lost to things like respiration and metabolism.

Plants are primary producers, which means they convert sunlight into energy. Herbivores, such as elephants, are primary consumers, converting plants they eat into energy.

At the top of the food chain are the predators, which eat herbivores and convert them into energy. But, Lewis noted, there's a 10 percent loss of energy at each stage removed from plants.

So "if you're living as a carnivore, you have to consume ten times as much to get the same amount of energy you would from eating at the primary level," Lewis explained.

A carnivore the size of an African elephant, for instance, would have to spend all its time hunting and eating animals its own size just to make up for that energy loss.

And after a while there wouldn't be much for it to hunt."

 

[Blobbenstein]

bit confusing....why does a carnivore have to consume ten times as much as a herbivore?

 

[flyingsnail]

Yeah, that doesn't make any sense, animal based foods are on average more caloric than plant based foods so why would a carnivore need to eat more? Plus there use to be very large carnivores.

 

[ledboots]

Yeah, that doesn't make any sense, animal based foods are on average more caloric than plant based foods so why would a carnivore need to eat more? Plus there use to be very large carnivores.

Because it is very expensive metabolically to digest meat. The large carnivores were likely reptiles, which don't need to use their metabolisms for temperature regulation, so can squander it on meat digestion. Like how alligators and crocs are so successful.

 

[flyingsnail]

Because it is very expensive metabolically to digest meat.

How so? Protein and fat are easy to digest....its plant matter that is difficult to digest.

The large carnivores were likely reptiles, which don't need to use their metabolisms for temperature regulation, so can squander it on meat digestion. Like how alligators and crocs are so successful.

The largest animals, both carnivores and herbivores, have been reptiles....but there have been very large carnivorous mammals. For example, orca whales are huge and are carnivorous.

 

[Clueless Git]

But, Lewis noted, there's a 10 percent loss of energy at each stage removed from plants.

So "if you're living as a carnivore, you have to consume ten times as much to get the same amount of energy you would from eating at the primary level," Lewis explained.

Someone needs to explain math to Lewis.

To compensate a ten percent loss you need a ten percent, not ten fold, increase.

In fact you don't even need math to know that's bollox.

If it weren't bollox then;

1. Eejyutts on, say, the Atkins diet would have to consume ten times the weight of meat and cheese that a vegan would need to consume in chickpeas and salad to obtain the same calories.

2. 100g of lettuce would have the same calorific value as 1Kg of steak.

 

[Blobbenstein]

you need to eat 11.11% more meat, by calories, than the prey animal eats in plants, by calories.

 

[flyingsnail]

After rereading the quote I think perhaps the guy is talking about how energy gets lost as it moves from plants to higher animals. At each stage of the food chain significant energy is lost because most energy goes to simply maintain the animal and when an animal (or plant) is consumed you're only recapturing a small fraction of his total energy intake. As such an ecosystem can support far more "primary consumers" than it can carnivorous animals. In terms of digestion the opposite is the case, animals that primary consume meat spend less energy on digestion than animals eating plants.

So I think the guy is saying something perfectly sensible....we were just interpreting it wrong.