As usual I've been following this post and find the discussion with everyone voicing their opinions very interesting. Considering my understanding of how the reptilian brain works I can't help but feel anthropocentrism (placing human attributes into animal behaviour) plays a huge role in our decisions toward the manner in which reptiles are kept in captivity.
It must be remember that animals (including reptiles) do not perceive time in a manner that is the same as humans. We contemplate the actions and decisions of our past and envision our actions in the future (episodic memory), whereby animals live in the present. They have what is referred to as a circadian oscillator which keeps track of their circadian cycles that are based on external clues such as temperature, day length, moon phases and celestial patterns which dictate activities such as sleep, reproducion, hibernation etc.
To address the original question, "'Do captive reptiles benefit from providing them with enrichment' (enhancing the quality of captive animal care by providing the stimuli for psychological and physiological well-being)? Personally, in regard to reptiles I'm not convinced (yet) that it plays that big a role.
Studies have proven that it is beneficial to higher order animals that are held in captivity but is it relevant to lower order animals such as captive held reptiles? Firstly I'd have to ask that given reptiles are primitive creatures with a primitive brain that is only concerned with survival, (i.e. shelter, food, water, reproduction, flight or fight responses) do they suffer from psychological conditions and boredom? Personally, unlike humans and other higher order animals, I doubt if they have the mental capacity to suffer from a psychological condition, stress or understand boredom. In fact considering physiological conditions contribute to chemicals released in a fight or flight response and that captive reptiles rarely if ever encounter the need to exercise the option I believe that it could be assumed that they don't suffer from stress at all. If it was the case that reptiles suffered from psychological conditions and stress as a result of physiological conditions couldn't it be assumed that it would be more prevalent in the wild state due to the continuous threat of predation and on-going concern with other survival factors?
I have no doubt that providing an enriched captive environment that emulates a reptile's natural environment allows the reptile to undertake activities conducive to those carried out in the wild state, but, do they need it to live contentedly in captivity? Given that when provided with the basic needs, it is obvious that those kept without the provision of a natural environment appear to survive and live long healthy lives it only leads me to ask if it is a necessity for their overall wellbeing or does it fall under a conscious category that allows the keeper the opportunity to feel more positive in the fact that they are keeping a native animal? Captive reptiles don't have the mental ability to sit around thinking..."I wish my cage had a more stimulating environment" or "I wonder what the outside world is like" or "I wish I had other things to do". Nor do they need it. As mentioned previously, reptiles do not lose their natural instincts when bred or held in captivity, so all things considered possessing the ability to contemplate on the past or envision the future could prove detrimental to a reptile's survival by wasting time with such thoughts as in the wild it would leave them open to being eaten and/or effect their time spent looking for mates.
Anyway, these are just my thoughts and I'd be interested to know what others think about the subject.
George.