This is a quite good interview with the philosopher Peter Singer, and presents similar views to those I've been persuaded to arrive at recently.
I particularly like his minimalist characterisation of 'leftist' thinking as "being concerned with eliminating the sufferings of others and of the oppressed" rather than being about "collective ownership"
Singer argues that people who care about ethics need to engage with evolutionary psychology/sociobiology and acknowledge the role played by evolution in creating certain general tendencies for human behaviour. This seems reasonable, if only to avoid characterisation
Perhaps it is better to be 'in the camp' in order to better critique the lazy genetic determinism, conflation of 'is' and 'ought', general to particular and, above all, unfalsifiable speculation
His argument is essentially a Humean one