There is a world somewhere between reality and fiction. Although ignored by many, it is very real and so are those living in it. This forum is about the natural world. Here, wild animals will be heard and respected. The forum offers a glimpse into an unknown world as well as a room with a view on the present and the future. Anyone able to speak on behalf of those living in the emerald forest and the deep blue sea is invited to join.
None of these are really examples of bad memory. Just that a lion starts concidering another lion as a outsider once enough time without contact has passed.
Keep in mind that a long lost brother is not less of a rival to a male lion than a complete stranger is. They arent going to say "thats uncle Furballs pride. Lets not take it over for families sake"
As for taking over natal prides. Even without mating opportunities, taking over a pride has its advantages to a male lion. So them taking their natal pride is not that odd.