There is value in performing “functional” or “whole body” types of movement. First, functional movements can save you time if you’re looking to exercise multiple parts without spending all day or week doing so. Second, life is whole body and functional, so exercises like deadlifting are likely to help when you need to carry heavy groceries or move a heavy object in the yard or around the house (or peek at a computer screen?). Third, our muscles tend to work together and not in isolation anyway, so even if you’re just going for big biceps or other beach muscles, you’re probably better off doing pullups as opposed to curls.
In any case, check out this great video of a 10-month-old kid doing pullups on the edge of a desk (kids, do not try this at home). Its pretty impressive and it looks like he might even have a bit of kipping going on. I don’t think it will be long before he’s riding that dog around the house.