Which animal is the best at processing its food?

Factual Questions
21

Sure, although of course they do have a metabolism, but you’re probably right - it’s a bit of a sidetrack from the letter of the OP.

22

IFRC small animals such as rabbits and guinea pigs (both quite tasty) are very efficient at conversion of input calories (1 input calorie ~ 0.3 output calories (of which some 50 percent can be consumed by you/me). Cattle are not very efficient at all ~ 5 %. Pigs are somewhere in the middle.

23

Given the right feed pigs hit 30% feed conversion efficiency, in other words for every two pound they are fed they will put on 1 pound of weight. Kangaroos are even beter because the have such small brains. However things like tortoises will beat any mammal simply because they don’t have to waste energy as heat.

24

Thats what the man said. Hydras effectively just sprout, like a hydra’s head.

25

That and the fact that they are topped with a bunch of tentacles…

26

This is an interesting point. A couple of questions might come out as a result of this:

We might be tempted to ask ourselves, “But what if we revised the question to consider what animal does the most ‘work’ with that 100% digested glucose calorie?” That is, who uses the highest portion of that energy for pushing a lever or locomotion or whatever, rather than simply ‘maintaining body temp and metaboic processes’?

If we could answer that, we might get closer to answering the OP. Of course, it’s still looks unanswerable (to me, anyway) because the percent of the calorie that goes toward work is going to vary greatly, depending upon the environmental conditions in which the animal finds itself: if we’re hanging around unclothed in the arctic, we’ll be using higher percentage of the glucose energy to keep warm than if we’ll walking around San Diego.

Maybe we could postulate the ‘ideal’ external conditions, whatever those may be (yet another unanswerable), and then apply an ‘amount of work’ per calorie formula to determine efficiecy, but we’re quickly getting toward so many complicating issues that I can’t really see it getting resolved satisfactorily.

So, there’s two cents off the top of my head. Someone please jump right in and elaborate or correct, as needed.

Pablito

27

So, to put it bluntly, owls don’t crap?

28

<Slip Mahoney>: " Okay, I’m convinced. What’s the best way to cook a mouse? "

There’s a good recipe in “Never Cry Wolf” by Farley Mowat. Never tried it myself, though… Let us know how it comes out.

29

Which animal is the best at processing its food?

Easy! The one with the best food processor!