The euphemism for bathroom stops was "does anyone want to check the tires". Of course you couldn't do that everywhere considering what might be lurking a few feet away. Once Philip actually went to check a tire which turned out to be losing air; these vehicles all carried two spares.
Polygamy is common in Tanzania. Philip told us that his father had 5 wives and he has 31 brothers and sisters. He had one wife and two children and that was all that he planned to have. Apparently his mother is very disappointed that he didn't have more wives and children. Polygamy in East Africa has various origins one of which was that the tribes and villages were at war with each other and many of the young men got killed such that there were many more women than men. Now that things are quite peaceful and access to education is more prevalent things will probably change more rapidly - probably a good thing since the population is increasing more rapidly than food production which is being hampered by water shortage.
Here we see Philip going to pick up a gall from a plant and soon show us the large colony of ants who live inside the galls. As a complex symbiotic arrangement, the galls on Acacia trees are a defense mechanism to prevent giraffes from eating the foliage since giraffes don't like ants.