Fisheries-induced evolution of alternative male life history tactics in Coho salmon.

Fisheries-induced evolution (FIE) can result when harvest imposes artificial selection on variation in heritable phenotypic traits. While there is evidence for FIE, it remains difficult to disentangle the contributions of within-generation demographic adjustment, phenotypic plasticity, and genetic adaption to observed changes in life history traits. We present evidence for FIE using dozens of Coho salmon () populations in which males adopt one of two age-invariant, heritable life history tactics: most mature as large three-year-old "hooknose" and typically fight for spawning opportunities, while some mature as small two-year-old "jacks" and fertilize eggs through sneaking.

Response to Durif et al.

Our recent study [1] in Current Biology used a magnetic displacement experiment and simulations in an ocean circulation model to provide evidence that young European eels possess a 'magnetic map' that can aid their marine migration. Our results support two major conclusions: first, young eels distinguish among magnetic fields corresponding to locations across their marine range; second, for the fields that elicited significantly non-random orientation, swimming in the experimentally observed direction from the corresponding locations would increase entrainment in the Gulf Stream system. In their critique, Durif et al.

A Magnetic Map Leads Juvenile European Eels to the Gulf Stream.

Migration allows animals to track the environmental conditions that maximize growth, survival, and reproduction [1-3]. Improved understanding of the mechanisms underlying migrations allows for improved management of species and ecosystems [1-4]. For centuries, the catadromous European eel (Anguilla anguilla) has provided one of Europe's most important fisheries and has sparked considerable scientific inquiry, most recently owing to the dramatic collapse of juvenile recruitment [5].

Host heterogeneity affects both parasite transmission to and fitness on subsequent hosts.

Infectious disease dynamics depend on the speed, number and fitness of parasites transmitting from infected hosts ('donors') to parasite-naive 'recipients'. Donor heterogeneity likely affects these three parameters, and may arise from variation between donors in traits including: (i) infection load, (ii) resistance, (iii) stage of infection, and (iv) previous experience of transmission. We used the Trinidadian guppy, , and a directly transmitted monogenean ectoparasite, , to experimentally explore how these sources of donor heterogeneity affect the three transmission parameters.

Sneaker Males Affect Fighter Male Body Size and Sexual Size Dimorphism in Salmon.

Large male body size is typically favored by directional sexual selection through competition for mates. However, alternative male life-history phenotypes, such as "sneakers," should decrease the strength of sexual selection acting on body size of large "fighter" males. We tested this prediction with salmon species; in southern populations, where sneakers are common, fighter males should be smaller than in northern populations, where sneakers are rare, leading to geographical clines in sexual size dimorphism (SSD).

Sequential female assessment drives complex sexual selection on bower shape in a cichlid fish.

In many animals, sexual selection on male traits results from female mate choice decisions made during a sequence of courtship behaviors. We use a bower-building cichlid fish, Nyassachromis cf. microcephalus, to show how applying standard selection analysis to data on sequential female assessment provides new insights into sexual selection by mate choice.

The accumulation of reproductive incompatibilities in African cichlid fish.

The rate at which different components of reproductive isolation accumulate with divergence time between species has only been studied in a limited, but growing, number of species. We measured premating isolation and hybrid inviability at four different ontogenetic stages from zygotes to adults in interspecific hybrids of 26 pairs of African cichlid species, spanning the entire East African haplochromine radiation. We then used multiple relaxed molecular clock calibrations to translate genetic distances into absolute ages to compare evolutionary rates of different components of reproductive isolation.

Morphological diversity and the roles of contingency, chance and determinism in african cichlid radiations.

Background: Deterministic evolution, phylogenetic contingency and evolutionary chance each can influence patterns of morphological diversification during adaptive radiation. In comparative studies of replicate radiations, convergence in a common morphospace implicates determinism, whereas non-convergence suggests the importance of contingency or chance.

Methodology/principal Findings: The endemic cichlid fish assemblages of the three African great lakes have evolved similar sets of ecomorphs but show evidence of non-convergence when compared in a common morphospace, suggesting the importance of contingency and/or chance.

When Rensch meets Bergmann: does sexual size dimorphism change systematically with latitude?

Bergmann's and Rensch's rules describe common large-scale patterns of body size variation, but their underlying causes remain elusive. Bergmann's rule states that organisms are larger at higher latitudes (or in colder climates). Rensch's rule states that male body size varies (or evolutionarily diverges) more than female body size among species, resulting in slopes greater than one when male size is regressed on female size.

Life-history variation and allometry for sexual size dimorphism in Pacific salmon and trout.

Allometry for sexual size dimorphism (SSD) is common in animals, but how different evolutionary processes interact to determine allometry remains unclear. Among related species SSD (male : female) typically increases with average body size, resulting in slopes of less than 1 when female size is regressed on male size: an allometric relationship formalized as 'Rensch's rule' . Empirical studies show that taxa with male-biased SSD are more likely to satisfy Rensch's rule and that a taxon's mean SSD is negatively correlated with allometric slope, implicating sexual selection on male size as an important mechanism promoting allometry for SSD.

Incorporating pathologists' criteria of malignancy into the evolutionary model for cancer development.

A wide variety of alterations in cell and tissue structure still form the basis for cancer diagnosis by pathologists. Cancer development is recognized to be an evolutionary process [Foulds, 1954; Cairns, 1975; Nowell, 1976; Sager, 1982; Tomlinson et al., 1996; Cahill et al.