I visited the Lansing zoo recently and was amazed that the sulcatas were out and about! The day was hot and humid; no need for a heat lamp. They have a fairly reasonable amount of space for stretching their legs here in Michigan. On "warmer" days in the winter when these guys are inside, I've seen cavies (mara) in this enclosure. You can easily see the plants they can't mow down. I'm not really sure why they can't access that center area. As far as I could see into the enclosure, there was no divider between the two tortoises, but it's quite dark under that awning.