Larger deer in northern regions
 

I was bummed to find the deer evolution thread shut down before I had a chance to reply.

My first thought was of the principle where animals that live farther north, grow bigger than animals in warmer climates due to the surface area to size ratio. Isn't this an evolved trait?

We all know you get an adult buck in saskatchewon and its going to be WAYYYYY bigger than the same aged buck in texas.

RE: Larger deer in northern regions
 

That is called Bergmanns Rule.

RE: Larger deer in northern regions
 

Southern deer don't have to contend with harsh winters.

RE: Larger deer in northern regions
 

Don't forget that their are nearly 40 subspecies of whitetail deer between central America and the northern reaches of Canada. I'm such a nerd.:eek:

Animals continually adapt to their surroundings.. Whitetail are perhaps the best at this. Whitetails in the north grow as big as 300 lbs., while the southern deer of the desert barely reach 100 lbs. I believe this is called evolution of a species.

By no means do I want this to turn into a religious debate...

RE: Larger deer in northern regions
 

i like my cornbelt deer!!!!

RE: Larger deer in northern regions
 

I thought it was Bergman's Law?

RE: Larger deer in northern regions
 

You guy's beat me to it with Bergmans Law or Rule.I was thinking I was going to dazzle everyone with my vast knowledge!:D

RE: Larger deer in northern regions
 

rybo .... it's adaptation ,,, not evolution

RE: Larger deer in northern regions
 

The good ole whitetailed deer, a fascinating example of 2.5million years of evolution at work...;).

RE: Larger deer in northern regions
 

Tony please stay out of my post since you got the other shut down. THanks.

RE: Larger deer in northern regions
 

Good post!

I think it's bulk up or die. A survival instinct in all living things.We all know deer are lazy and will only go out of their way if they have too. Up north they have too.

RE: Larger deer in northern regions
 

Its not about just northern species eating more, its a physiological trait that the bigger animals survive to pass on thier genes.

RE: Larger deer in northern regions
 

I'd say your both are right. People seem to be getting bigger and better nutrition is give as a reason. Record deer are as well and nutrition is also part of the equation.

RE: Larger deer in northern regions
 

Call me a dim bulb, but what isBergmann's Rule? It doesn't sound familiar.

RE: Larger deer in northern regions
 

I think to some extent you all are right on some parts of this. First is the beech nuts and acorns that build mass. This mass is very much needed to help the deer through the rut and harsh winters. Second they are always moving around to aviod the predators. That is alot of running and jumping over brush pile and old logs ect. I think all this running and moving around creates longer deer. All our heavey weights are long deer, Also there is not much for corn and soy bean plantations up this way so it is mostly grass and apples as well as a few wild berries instead. Here a food plot in the woods could easily cause the deer's downfall. As they would group up and make it easy for predators to attack them. During times of heavey snowfall we lose alot of deer as they are crowded up into deer yards that make it easier for them to move around in deep snow. Anyways you get the idea.

RE: Larger deer in northern regions
 

not to mention a large deer would have trouble with the heat extremes in the south and are much better off being smaller

RE: Larger deer in northern regions
 

Bergmann's Rule
In 1847, Carl Bergmann observed that within the same species of warm-blooded animals, populations having less massive individuals are more often found in warm climates near the equator, while those with greater bulk, or mass, are found further from the equator in colder regions. This is due to the fact that big animals generally have larger body masses which result in more heat being produced. The greater amount of heat results from there being more cells. A normal byproduct of metabolism in cells is heat production. Subsequently, the more cells an animal has, the more internal heat it will produce.
In addition, larger animals usually have a smaller surface area relative to their body mass and, therefore, are comparatively inefficient at radiating their body heat off into the surrounding environment. The relationship between surface area and volume of objects was described in the 1630's by Galileo. It can be demonstrated with the cube shaped boxes shown below. Note that the volume increases twice as fast as the surface area. This is the reason that relatively less surface area results in relatively less heat being lost from animals.
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Comparison of cube surface areas and volumes illustrating Bergmann's rule[/align][blockquote]
Polar bears are a good example of this phenomenon. They have large, compact bodies with relatively small surface areas from which they can lose their internally produced heat. This is an important asset in cold climates. In addition, they have heavy fur and fat insulation that help retain body heat.
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Negative correlation between environmental temperature
and body mass in warm blooded animals
Massive polar bear bodies are
predicted by Bergmann's rule[/align]Bergmann's rule generally holds for people as well. A study of 100 human populations showed a strong negative correlation between body mass and mean annual temperature of the region. In other words, when the air temperature is consistently high, people usually have low body mass. Similarly, when the temperature is low, they have high mass. However, there are exceptions.
A corollary of Bergmann's rule stated that a linear shaped mammal will lose heat to the environment faster than a more compact one of similar size. The boxes below illustrate this fact. Note that the long, narrow box has the same volume but greater surface area. It is comparable to a tall, slender animal.
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[/align][/blockquote]