Animal trainers

[paul cooper]

(12-04-2015, 06:21 PM)peter Wrote: 2 - Captive big cats

Most posters don't seem to realize that captivity has profound consequences. Those who top the food chain in particular are affected. The reason is big predators do not get the opportunity to learn and develop. In many respects, they remain infants all their life.    

A century ago, authorities already noticed that captive tigers, in zoos all over the world, were mere shadows of their wild relatives. Parodies. The most likely reason is no exercise and no development whatsoever. Another is those who breed them have very little knowledge. As there was nobody to stop them, they just crapped around. The consequences were profound.  

Tigers are more affected by captivity than lions. Here's why. Adult wild tigers are professional big game hunters. Learning how to hunt and how to overcome resistance of very powerful animals on your own takes a lot of time. It also is dangerous. Those who make mistakes not seldom perish. Those who learn how to hunt and reach adulthood than have to learn how to earn and defend a territory. When they succeed and keep it up for a few years, they will breed. This means that only the best breed. In captivity, the essence of tigers is lost. And it shows. In captive tigers, you still see the fundaments of what a tiger is supposed to be. It takes a long time to affect the bones and structure, but muscles are affected immediately. Same for mental development.

Lions, in contrast to tigers, are social big cats. In captivity, they also live in prides. Hunting skills, of course, are lost, but social skills are not. Males in particular interact in more or less the same way as their wild relatives. This mean they, in contrast to tigers, face competition. Nearly everything they do is affected by it. Males strive for dominance, they eat first and they often fight, just like their wild counterparts. As they don't need energy to hunt anymore, chances are the extra energy is invested in competition. Captive male lions, if anything, are even more aggressive than their wild counterparts. Will captivity affect their body? Of course it does, but not to the degree seen in tigers. As they don't need to hunt anymore and eat enough (not always true for wild male lions), there's no need for athletic bodies and endurance anymore. Compact and robust bodies would be much more appropiate for captive male lions and that's what we get. Although there's no reliable information, my guess is captive male lions are more robust and heavier than their wild relatives.

All in all, the conclusion is that captive tigers degenerate and keep on degenerating. After some generations, you will see a parody on a wild tiger. This is not the case for captive male lions for the reasons mentioned above. Does it show in captive animals? Yes. Although a bit shorter, captive male lions generally are more robust and heavier than male tigers at equal length. Although there are plenty of exceptions, I saw it time and again. My guess is this could be the general rule in captive lions and tigers all over the world.            

This should back you up:
"In order to detect tiger genes evolving under positive selection, we used the conserved genome synteny methodology19 (between human and other mammalian species (cat, dog, mouse and panda)) and a branch-site likelihood ratio test (Methods). A total of 178 positively selected genes out of 7,415 high-quality ortholog genes were identified in the Amur tiger (Supplementary Table S35, Supplementary Data 1). Functional categories for positively selected genes were over-represented in muscle filament sliding (GO:0030049, P=0.0049, Fisher's exact test, MYH7, TPM4 and TNNC2), filamentous actin (GO:0031941, P=0.0062, TPM4 and MYO1A) and stress fibre (GO:0001725, P=0.0039, MYH7, TPM4 and ACTN4) (Supplementary Table S36, Supplementary Data 2). We also identified GO categories, which are evolving under significantly high constraints19 (Supplementary Tables S37–S39, Supplementary Methods). Significantly altered Ka/Ks ratios of non-synonymous to synonymous substitutions for GO categories (P<0.01, Binomial test) revealed evidence of rapid evolution in the tiger for muscle strength (muscle contraction and actin cytoskeleton), energy metabolism (GTPase activity, ATP binding and energy reserve metabolic process), and sensory nerves (G-protein coupled receptor activity, olfactory receptor activity, visual perception and nervous system development)"
https://www.nature.com/articles/ncomms3433
The specimen used was a 9 year old male amur tiger from Everland zoo.
Go to table S42 to see everything.. https://images.nature.com/original/natur...433-s1.pdf
Interesting to see.

Obviously they are evolving for the worse. Use it or lose it. Reply