keach: nopal still grows just outside the cave. macneish's workmen remember droughts when they ate nopal to stave off hunger and thirst. they call the cactus "starvation food." so, discovering cactus in the cave tells the archaeologists it was occupied during the dry season when both food and water were scarce. pretty good, not bad. needs a little sauce. the most precise evidence that this was a dry-season camp is a tiny, hollow bone. interpreter: this is the bone of a bird, perhaps a duck, which migrates to this region each year only in the winter during the dry season. all this is evidence of the food that they had in this cave and indicates that it was occupied in the dry season in autumn and winter. keach: until recently, another living culture was still following a nomadic way of life. these are the kung bushmen of south africa. they provide some clues as to what daily life might have been like in the ancient tehuacan valley. [ thunder ] in the rainy season, the desert blooms. the men hunt and the women gather nuts and berries

so why wouldn't you want to keach a guy like that? i mean, i'm excited to coach him, and hopefully he is excited to play here. >> now that's an endorsement. so he's got to meet the quarterback. that's the first thing. but second, he's got to figure out who will be the assistants. as of now, jim has let, raheem morris, sean mcvay are on the staff as coaches. gruden says he wants to continue evaluating. that way he puts the best coaches in charge. >> i'm going to wait and see. i'm going to interview a lot of coaches. like you said, i'm going look at each coach that has been retained by bruce here, and interview everybody. and make sure that i know there is a lot of coaches here that can coach. and there a lot of good football people here that can coach there is also good football people across the country right now looking to work, and looking to work for the washington redskins. i don't think finding a great coach and coaching staff is going to be difficult. it's finding the right ones that fit what i want to do and what the players wa

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