Taxonomic Chauvinism Revisited: Insight from Parental Care Research

Parental care (any non-genetic contribution by a parent that appears likely to increase the fitness of its offspring) is a widespread trait exhibited by a broad range of animal taxa. In addition to influencing the fitness of parent(s) and offspring, parental care may be inextricably involved in other evolutionary processes, such as sexual selection and the evolution of endothermy. Yet, recent work has demonstrated that bias related to taxonomy is prevalent across many biological disciplines, and research in parental care may be similarly burdened. Thus, I used parental care articles published in six leading journals of fundamental behavioral sciences (Animal Behaviour, Behavioral Ecology, Behavioral Ecology and Sociobiology, Ethology, Hormones and Behavior, and Physiology & Behavior) from 2001–2010 (n = 712) to examine the year-to-year dynamics of two types of bias related to taxonomy across animals: (1) taxonomic bias, which exists when research output is not proportional to the frequency of organisms in nature, and (2) taxonomic citation bias, which is a proxy for the breadth of a given article—specifically, the proportion of articles cited that refer solely to the studied taxon. I demonstrate that research on birds likely represents a disproportionate amount of parental care research and, thus, exhibits taxonomic bias. Parental care research on birds and mammals also refers to a relatively narrow range of taxonomic groups when discussing its context and, thus, exhibits taxonomic citation bias. Further, the levels of taxonomic bias and taxonomic citation bias have not declined over the past decade despite cautionary messages about similar bias in related disciplines— in fact, taxonomic bias may have increased. As in Bonnet et al. (2002), my results should not be interpreted as evidence of an ‘ornithological Mafia’ conspiring to suppress other taxonomic groups. Rather, I generate several rational hypotheses to determine why bias persists and to guide future work

Parental-care parasitism: how do unrelated offspring attain acceptance by foster parents?

In this review, we describe a new term, "parental-care parasitism", that we define as the interaction in which an individual (the parasite) obtains reproductive benefits while reducing or completely eliminating its own costs of parenting by exploiting any type of offspring care provided by other individuals (the hosts). Parental-care parasitism comprises parasitic behaviors ranging from interactions in which just the nest is taken over to those where various combinations of nest, food and offspring care are parasitized. We subdivide parental-care parasitism into 3 categories depending on the strategy used by the parasite to reach host nest: 1) the parasite approaches the nest during host absence, 2) parasite and host adults meet at the nest but no aggression is carried out, or 3) the host tries to evict the parasite at the nest. We also discuss the costs and benefits for both parents and offspring, as well as for hosts and parasites, placing different forms of parental-care parasitism in an evolutionary context within the frameworks of both parental investment theory and coevolutionary arms race theory. Herein, we thoroughly discuss the lack of offspring discrimination found in some species, some populations of the same species and some individuals within the same population on the basis of the coevolutionary arms race theory, and the fact that unrelated offspring attain acceptance by foster parents, contrary to the general predictions of parental investment theory. This review offers a conceptual framework that seeks to link parental investment theory with coevolutionary arms race theory. Copyright 2011, Oxford University Press.