Does offspring sex ratio differ between urban and forest populations of great tits (Parus major)?

Ágh, Nóra and Pipoly, Ivett and Szabó, Krisztián and Vincze, Ernő and Bókony, Veronika and Seress, Gábor and Liker, András (2020) Does offspring sex ratio differ between urban and forest populations of great tits (Parus major)? Biologia Futura, 71 (1-2). pp. 99-108. ISSN 2676-8615 (print), 2676-8607 (online)


Download (907kB) | Preview


Since male and female offspring may have different costs and benefits, parents may use sex ratio adjustment to increase their own fitness under different environmental conditions. Urban habitats provide poorer conditions for nestling development in many birds. Therefore, we investigated whether great tits (Parus major) produce different brood sex ratios in urban and natural habitats. We determined the sex of nestlings of 126 broods in two urban and two forest sites between 2012 and 2014 by molecular sexing. We found that brood sex ratio did not differ significantly between urban and forest habitats either at egg-laying or near fledging. Male offspring were larger than females in both habitats. This latter result suggests that male offspring may be more costly to raise than females, yet our findings suggest that urban great tits do not produce more daughters despite the unfavourable breeding conditions. This raises the possibility that other aspects of urban life, such as better post-fledging survival, might favour males and thereby compensate for the extra energetic costs of producing male offspring.

Item Type: Article
Subjects: Q Science / természettudomány > Q1 Science (General) / természettudomány általában
Q Science / természettudomány > QH Natural history / természetrajz > QH301 Biology / biológia
Depositing User: Zsolt Baráth
Date Deposited: 12 Oct 2022 13:44
Last Modified: 12 Oct 2022 13:44

Actions (login required)

Edit Item Edit Item