Rearing Success Does Not Improve With Apparent Pair Coordination in Offspring Provisioning

Abstract

In species with biparental care, behavioral coordination in the provisioning of the progeny is hypothesized to increase the number of offspring that survive to independence. Coordination is often quantified by two metrics, alternation and synchrony. Turn-taking (leading to an alternation pattern) can result when one parent's investment strategy is based on the investment of its partner (i.e., conditional cooperation). This should increase the overall provisioning rate and improve offspring body condition. Synchrony might equalize food delivery among offspring and therefore decrease the variance in offspring body condition within the brood. Overall, offspring survival could be increased by parental coordination. Finally, pairs with low coordination, and with potentially lower reproductive success, are expected to be more likely to divorce. In this study, we use a dataset on 473 pairs of house sparrows in a natural insular population to test these hypotheses. We found no effect of the pair's apparent coordination on offspring condition, offspring survival, or divorce rate, questioning the adaptive significance of this behavior. We argue that, in this species, the detection of a higher frequency of alternation and synchrony, when compared to chance expectation, might be induced by the environment, rather than result from an emergent pair behavior selected for fitness benefits.

Urban resources limit pair coordination over offspring provisioning

“…In this respect, we found that suburban pairs fledged lighter chicks. However, it is notoriously difficult to assess the impact of reduced alternation alone on offspring fitness in correlative studies 72,73 , especially in situations in which fledgling weight is also likely to be function of provisioning rate, food availability and habitat composition such as in this study. Experimental manipulations of one parent's investment (e.g.…”

Genetic and Social Transmission of Parental Sex Roles in Zebra Finch Families

“…Mariette and Griffith, 2012). Synchronized, rather than independent nest visits may reduce sibling competition through more equal food distribution between offspring or decrease the chance of depredation as a result of lower number of overall nest visits (Shen et al, 2010;Mariette and Griffith, 2012;Leniowski and Wegrzyn, 2018;Wojczulanis-Jakubas et al, 2018;Ihle et al, 2019). In addition, synchronized provisioning behaviour might be the result of other, nonparental activities, for instance foraging patterns (Masello et al, 2006).…”

Machine learning pipeline extracts biologically significant data automatically from avian monitoring videos

“…Between 2004 and 2015, videos (N=2112) were manually annotated by postgraduate students and researchers, which contributed to multiple publications (see Ihle et al, 2019;Nakagawa et al, 2007;Schroeder et al, 2019Schroeder et al, , 2016Schroeder et al, , 2013Schroeder et al, , 2012. We used these data as a baseline -the 'manual feed rate' -to be compared against the automatically-collected data ('automatic feed rate') outlined below.…”

“…As such, a large body of literature focuses on how nest visit frequency with dependent young is associated with aspects of an animal's life history, with a focus on birds, where 90% of species engage in parental care (Cockburn, 2006). For example, work on life history trade-off in terms of parent and offspring fitness (Schroeder et al, 2013), parent coordination (see Ihle et al, 2019;Wojczulanis-Jakubas et al, 2018), parent-offspring conflict (Estramil et al, 2013), or ageing (Wilcoxen et al, 2010) all used the frequency of parental visits to nests (or provisioning) as a proxy of parental investment.…”