Live-bearing lizard mates
The more often they have mated, the more choosy female viviparous lizards become. Though the 'quality' of the male doesn't matter to females for their first pairing, they are much more critical when accepting their next mate.
Live-bearing lizards (Zootoca vivipara) reproduce only two or three times. For the first mating, the female is not at all picky, and will accept any male. This changes after the first fertilisation. The female becomes critical and goes searching for a male that is genetically as different as possible from herself. After bearing her first young she looks for a mate that can provide even better offspring. Interestingly, it is not completely clear how females recognise a ‘good’ mate. A possibility suggested by the researchers is that the male’s scent tells the female something about the genetic material he has to offer.
The results of this study can be found in the journal Behavioural Process.