Tibetan ground-tits, new study


This video says about itself:

Groundpecker [=ground tit] (Pseudopodoces humilis) Juveniles’ Behavior

Date: 17 August 2012

Location: Polokangka La, Ladakh, India

From Animal Behaviour:

Cuckolded male ground tits increase parental care for the brood

Highlights

Polyandrous females benefit from reduced workload in brood provisioning.

• Polyandrous females produced young with larger extrapair partners.

• Cuckolded males increase parental care for the brood with mixed paternity.

• Polyandrous females’ paternity allocation determines cuckolded males’ responses.

Extrapair copulations (EPCs) occur widely in socially monogamous birds. How cuckolded males respond to the infidelity of their social mates is still problematic. We addressed this question in the ground tit, Pseudopodoces humilis, in which EPCs occur frequently and successful reproduction relies on biparental care. In solitarily breeding pairs, we calculated the feeding rate of social pairs at polyandrous and monogamous females’ nests. Compared with that at monogamous nests, cuckolded males increased their feeding rate whereas polyandrous females reduced theirs.

Polyandrous females had larger extrapair partners, although their extrapair young were neither heavier nor had higher heterozygosity than their within-pair young. Extrapair males never provided paternal care for the mixed brood and polyandrous females had no opportunity to forage on the territory of extrapair males. Therefore, the energetic benefit polyandrous females obtained was due to the increased parental care of their social mates. Even losing some share, cuckolded males still gained most of the paternity within the mixed brood. By increasing parental care for the current brood, they could ensure the survival of their own offspring.

Thus, we suggest that females place their social male in a cruel bind by creating a larger brood containing some unrelated young: if the social male does not step up provisioning to meet the demands of the larger brood, overcrowding may reduce the survival of his offspring. Polyandrous females maintain the fitness incentive for their social males to provide parental care by limiting the paternity of extrapair males to a minority of the brood.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.