Questions about Rhinoceros Beetles

[Gardamorg]

What makes Rhinoceros Beetles so strong? Do they have super strong muscles? And could a human acquire such muscles if he/she a similar genetic make up?

What is the strongest genus of the Rhinoceros Beetles? Hercules Beetles, Atlas Beetles, Ox Beetles, Princess Beetles, ect...

If its possible, I'd rather you give me a link to a page where I could read everything there is to know (Or close to it) about Rhinoceros Beetles, that would also answer all of the questions above and more. I tried Wikipedia, it's not very specific or explanatory.

Were there ever any animals, dinosaurs or prehistoric creatures of any kind proportionately and physically stronger animals than Rhinoceros Beetles?

[orbsycli]

I think gravity affects the strength to size ratio greatly. Take that into consideration....but I'm by no means an expert or anything.

[CraigD]

Originally Posted by Gardamorg

What makes Rhinoceros Beetles so strong?

First, we should note that, as was mentioned in an earlier thread, The Rhino Beetle isn’t strong in an absolute sense (by the only reliable account I’ve yet read, it can lift about 0.24 kg) only in proportion to its mass (at around 0.00238 kg, the beetle can carry a maximum of about 100 times its own weight, and up to about 30 times its own weight at its usual walking speed, about 0.01 m/s). After all, this is a bug we’re talking about – a really big one, but nowhere near the mass of a animal like a human being (around 80 kg).

Note that the 1995 experiment by Roger Kram described in this 1995 paper, (the source of most of the data in this post) don’t support the claim that this big beetle can “lift 850 times its own weight” common to sources like this wikipedia article and the Smithsonian site it cites. Rather, the limit appears to be closer to 100 times its weight. I’m curious where the “850” comes from. Other than this 1996 Discover magazine article, which describes Kram’s experiment and draws the same conclusion I do – that the Rhino Beetle can only support about 100 times it weight - I can’t find any scientific verification or comment on the “850 times” claim.

So it’s possible that the Rhino Beetle’s claim to being the proportionally strongest animal in the world is false, or at least greatly exaggerated.

Originally Posted by Gardamorg

Do they have super strong muscles?

To the best of my knowledge, no.

Their high strength-to-mass ratio appears to be the result of having very efficient lifting/walking parts – in short, that they’re evolutionarily adapted to moving under heavy loads. These beetles don’t normally actually carry loads, but they burrow in wood, so need this strength to do so quickly and without using too much energy.

What’s most remarkable about the Rhino Beetle is not the maximum weight it can lift, but that, for weights up to about 30 times (but not 40 times) its own, it can carry them for long periods at about it’s usual walking speed. Measurements of the amount of oxygen consumed by the beetle while doing this indicate that, while carrying 30 times its weight, it’s only working about 4 times as hard (4 times its normal metabolic power). Usually, an animal must work about 2 times as hard to carry its own weight, 4 times as hard to carry 3 times its weight, etc.

As far as I know, the exact mechanics of how Rhino Beetles and similar arthropods get this mechanical efficiency is not well understood. I suspect the explanation is analogous to how a human being can move a heavy load with little additional effort using a hard cart – the beetle can be thought of as having a “machine” analogous to a human’s artificial kind built into its anatomy.

Originally Posted by Gardamorg

And could a human acquire such muscles if he/she a similar genetic make up?

For all intents and purposes, human beings do have the same muscle genes as beetles – or birds, elephants, whales, slugs, sloths.

The main proteins involved in muscles are actin, the cadherins, and the catenins. These proteins, and the genes that code them, are among the most “conserved” in nature – the protein is about 95% identical between humans as yeast, the genetic sequences that code for it 80% identical. Between insects and humans, the similarity should be even greater.

The bottom line here is that strength in animals is less a matter of the cellular makeup of muscles than the arrangement of them, and the skeletal “machinery” that allows them to do work. Natural selection has assured that beetles have good anatomies for burrowing in wood, humans for walking, running, and carrying things, elephants for walking and foraging food, etc. We humans have the additional trick of making machines that give our muscles mechanical advantages our skeletons can’t. Even without the more recent human trick of using engines to replace muscle power, we’re capable of making machines that allow us to lift weights hundreds or even thousands of times our own, while the Rhino beetle, amazing as it is, is limited to the “machines” that come built in to it.