Comments on: Metabolism and power laws

By: arizona student

arizona student — Tue, 29 Sep 2009 00:24:30 +0000

This helped me for my ecology exam. Thanks!

By: Gregorio

Gregorio — Wed, 02 Sep 2009 20:38:27 +0000

And it’s all wrong! Geoffrey West and the clowns at Santa’s Fey Institute have been able to perpetuate bunk for over a decade now because, as formulated, it has no consequence and can make no predictions. I recommend the essay at the site Theoretical Biology and Medical Modelling entitled “The terrestrial origins of metabolism and life – by the numbers” for a treatment of allometric scaling that clearly suggests West, Brown and Enquist are way off the mark. This treatment of the issue generates numerous, testable deductive inferences. The bell has wrung. It’s time for the old guard to leave the stage and turn the future over to the young.

By: ekzept

ekzept — Mon, 01 Jun 2009 02:46:07 +0000

Sorry posting from different computers and cookie sets: ekzept == Jan Theodore Galkowski

By: ekzept

ekzept — Mon, 01 Jun 2009 02:44:43 +0000

BTW, Vogel’s COMPARATIVE cites a 1961 Kleiber, THE FIRE OF LIFE, AN INTRODUCTION TO ANIMAL ENERGETICS, Wiley, on his page 45. Chapter 3 of COMPARATIVE is devoted to “Size and Scale”.

Oh, and to “Second, all animals have an interior surface area – the lungs. Does the surface area of the lungs track the product of metabolic rate and animal weight?”, strictly speaking, lungs are part of the OUTSIDE surface area, as is the alimentary canal.

By: Sue VanHattum

Sue VanHattum — Sun, 31 May 2009 21:31:12 +0000

This reminds me of On Being the Right Size, by J.B.S. Haldane, written in 1928, and online here: http://irl.cs.ucla.edu/papers/right-size.html

Have you read it?

By: Qual é a potência do seu metabolismo? « Comentários, Críticas, Dicas etc.

Qual é a potência do seu metabolismo? « Comentários, Críticas, Dicas etc. — Mon, 04 May 2009 18:48:24 +0000

[...] de Metabolism and power laws — The Endeavour. Postado em Biologia, Ciências, Química, Saúde. Tags: ecologia, metabolismo. Nenhum [...]

By: Mathematics Carnival 51 - squareCircleZ

Mathematics Carnival 51 - squareCircleZ — Fri, 24 Apr 2009 15:41:49 +0000

[...] Cook inspires us to consider some math behind elephants and mice in Metabolism and power laws. When not blogging, John works in a cancer clinic. Blog home: The [...]

By: Jan Theodore Galkowski

Jan Theodore Galkowski — Tue, 21 Apr 2009 19:58:42 +0000

I’m fascinating by this stuff and have found biometrician Steven Vogel’s works on comparative biomechanics most approachable and interesting. He began with LIVE IN MOVING FLUIDS and went on from there. I have bought copies of his VITAL CIRCUITS for 5 physicians. He has a textbook called COMPARATIVE BIOMECHANICS which discusses exactly this point. I he’d disagree that “Trying to derive a single formula is a nearly meaningless exercise” because from such attempts, much can be learned about biology-in-the-large, even if a particular species might be odd.

I’m about to launch into his CAT PAWS AND CATAPULTS, BTW.

By: Preston L. Bannister

Preston L. Bannister — Sat, 18 Apr 2009 21:21:05 +0000

The “power law” strikes me as not very meaningful.

Each animal is a different design. An elephant is not just a very big mouse. The design is different, and the differences are likely tied to heat control.

Thinking about elephants in warm climates – there are two aspects to the design of an elephant that increase surface area (and allow for heat loss). First, elephants seem generally to have rather large ears, and the ears could be very effective heat radiators (what does a thermal picture of an elephant look like?). Second, all animals have an interior surface area – the lungs. Does the surface area of the lungs track the product of metabolic rate and animal weight? Is the respiratory system designed to conserve or expel heat? My guess is we get different answers for different animals.

How would an ice-age mastodon compare to a modern tropical elephant? Would the metabolic rates differ? Would the large ears disappear? Would the design of the respiratory system change to conserve heat?

Can evolution force relatively rapid change in metabolic rates, or is this design aspect only very slow to change? The metabolic rates of large tropical and polar dinosaurs would be interesting to know – but that data will be hard to obtain.

Yes, as a rough average, the metabolic rates of large animals have to be lower than small animals – but individual differences in design (driven by successful ecological niches) are going to move the data points around quite a lot. Trying to derive a single formula is a nearly meaningless exercise.

There is perhaps an interesting bit of data to be derived from metabolic rates. Assuming that changes to cell chemistry are slow on an evolutionary time scale (a big assumption that needs testing), then similar metabolic rates might provide a measure of genetic distance between species.

By: Jon Ingram

Jon Ingram — Thu, 16 Apr 2009 17:26:50 +0000

Thank you for the interesting post. You’ve motivated me to put ‘Complexity’ on pre-order (it isn’t yet out in the UK). If I could get hold of some of the data, it would certainly give some purpose to the ‘draw a line of best fit’ lesson.