What makes an animal’s coat and fur go from flat in the summer to full and luxurious in late fall and winter? Surely it has to be diet change adding fat and nutrients? Or is it something in the actual season change? This could be a very simple answer or something very scientific that I actually never really thought about before.
Gonna dig out my big expensive book and see if I can’t find out.

Hours of daylight, or lack of actually.

That is crazy. Like sort of seasonally induced ovulation in cats.
All things governed by the moon and the tides.

Photoperiodisam and Bergmann's rule to a lesser extent

Exactly the lack of daylight triggers the pinal gland also known as the third eye to produce a hormone melatonin.

The weather or cold has nothing to do with it but is more of consequence of shorter daylight..

Bermann's rule is more about the size of the animal in comparison of how far north it exisits.

Elevation on mountains also is part of Bergmann's rule from what I understand of it

Outstanding , eager to share this with my work crew.

Pineal gland. All mammals have some form of a pineal gland, it's more or less an internal clock based upon daylight received.

In humans it is associated with the "holiday blues" that affect some during winter.

You can actually keep a horse from getting its winter coat by leaving lights on it in the barn at night.

When we would take our horses and mules elk hunting in September they would start to hair over in two weeks. At home it was late November before they started to get shaggy. Kind of cool.

If critters waited for cold weather it would be too late in most cases.

I've always wondered how animals that den up during the day, so they don't experience any daylight, can be effected by less daylight, that they aren't experiencing. There has to be more to it.

Keith

Saw a study once of whitetail deer. Control group were left in total UV sunlight 24 hours a day. Some of the bucks actually grew 2 or three sets of antlers.

It took me half an hour to find this post...

so you better go read it!!! LOL

EXCELLENT post on the topic.

https://trapperman.com/forum/ubbthreads.php/topics/851620/1

When i w3as involved with ranch fur ( fox) we kept all the pelters in the dark fur sheds.

Nine pages dang I better get busy!!!

Already reading. Noting many many names I do not recognize. Additionally, they all sound………smarter

There are a lot of great people on that thread that are no longer here, and a lot of great people that still are. Some are dead, some just left for some reason or another.

One of the better conversations ever had on here... in my opinion.

Pay attention when white and don wolf (deceased) talk....

Always wondered how the same condition effects humans... it has to trigger something?
I know for fur trappers it triggers a desire to be outdoors and to set steel...lol

Wait a second... are you saying we're dumb??

I’m saying this is the most intelligent conversation I’ve ever seen on T man!!