Great question! I suppose the complexity of their interactions and their similarities with humans - so much politics. I also love seeing how traits are passed down through family lines - not just physical traits; but mothering skills etc.
Wellington Zoo has a female named Cara, who was born 1981 at Taronga Zoo. Cara wasn’t a careful mother, she lost two of her four offspring when they were a few months old due to her lack of maternal care. She would leave them laying on the floor and they unsurprisingly sustained injuries from the other chimps. I later learned that Cara’s own mother was described as ‘scatterbrained’ and lost one of her offspring under near identical circumstances.
Cara and her unnamed infant (that died from injuries caused by other chimps) in 2003. Photo credit to
@Simon Hampel:
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