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Biodiversity loss and anthropogenic modifications to species communities are impacting the frequency and magnitude of disease emergence events. These changes may be related through mechanisms in which biodiversity either increases (amplifies) or decreases (dilutes) disease prevalence. Biodiversity effects can be direct, when contacts among competent hosts are replaced by contacts with sink hosts, or indirect through the regulation of host abundances.Here, we introduce a multihost compartmental disease model, weighting host competences by their evolutionary relatedness. Our model simulates host communities with substitutive and additive assembly patterns and frequency‐ and density‐dependent pathogen transmission modes, from which we estimate the community disease outbreak potential R0.Simulations show how differences in phylogenetic structure can switch host communities from diluting to amplifying a disease, even when species richness is unchanged. We additionally show that phylogenetic dilution can occur simultaneously with (classic) amplification through species richness.We illustrate our model using empirical data describing the relationship between phylogenetic distances separating hosts and their likelihood of disease sharing. Our study demonstrates how host evolutionary histories can drive disease dynamics through a phylogenetic dilution effect. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Several studies have demonstrated that zebra finches (Taeniopygia guttata) prefer their fathers' songs over unfamiliar songs. Songs of tutors (i.e., fathers) and tutees (i.e., sons) resemble each other as a result of cultural transmission. Subjects (N = 18) with a previously established preference for the father's song could choose between the song of an unfamiliar brother or a random unfamiliar song in an operant task. Most subjects showed a significant preference for either category of song, but overall, the songs of unfamiliar brothers were not preferred, although they were more similar to the father's song than were the unfamiliar songs. This suggests that subjects did not generalize their learned preference for a song of a particular tutor to the songs of his tutees.

Dispersal is an important form of movement influencing population dynamics, species distribution and gene flow between populations. In population models, dispersal is often included in a simplified manner by removing a random proportion of the population. Many ecologists now argue that models should be formulated at the level of individuals instead of the population level. To fully understand the effects of dispersal on natural systems, it is therefore necessary to incorporate individual‐level differences in dispersal behavior in population models. Here, we parameterized an integral projection model, which allows for studying how individual life histories determine population‐level processes, using bulb mites, Rhizoglyphus robini, to assess to what extent dispersal expression (frequency of individuals in the dispersal stage) and dispersal probability affect the proportion of successful dispersers and natal population growth rate. We find that allowing for life‐history differences between resident phenotypes and disperser phenotypes shows that multiple combinations of dispersal probability and dispersal expression can produce the same proportion of leaving individuals. Additionally, a given proportion of successful dispersing individuals result in different natal population growth rates. The results highlight that dispersal life histories, and the frequency with which disperser phenotypes occur in the natal population, significantly affect population‐level processes. Thus, biological realism of dispersal population models can be increased by incorporating the typically observed life‐history differences between resident phenotypes and disperser phenotypes, and we here present a methodology to do so. [ABSTRACT FROM AUTHOR]