Pronoun problems

The passage below is from ‘the Blank Slate’ by Steven Pinker.

http://evolbiol.ru/blankslate/blankslate.htm

But it is the doctrine of the Noble Savage that has been most mercilessly debunked by the new evolutionary thinking. A thoroughly noble anything is an unlikely product of natural selection, because in the competition among genes for representation in the next generation, noble guys tend to finish last. Conflicts of interest are ubiquitous among living things, since two animals cannot both eat the same fish or monopolize the same mate. To the extent that social motives are adaptations ?that maximize copies of the genes ?that produced ?them, ?they should be designed to prevail in such conflicts, and one way to prevail is to neutralize the competition.

In this passage, I’m not sure what the underlined pronouns stand for.
I have my answers, but I want to double check.

?that : adaptations
?that : the genes
?them : social motives
?they : I’m in a dilemma between ‘the genes’ and ‘social motives,’ though I’m leaning toward ‘the genes.’

Regards.