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The snapping shrimp, Synalpheus regalis, lives in colonies with a single reproductive female, in the internal canals of sponges on Caribbean coral reefs. Most members function as non-reproductive workers who protect and defend their sponge against intruders. The shrimps have a snapping major fighting claw which is as effective as the sting in Hymenoptera. Males and females are however diploid in contrast to Hymenoptera in which males are haploid. Cavities appear to favor sociality by keeping relatives together.

Author(s): Nancy Moran [1]; Naomi Pierce [2]; Jon Seger [3] William Donald Hamilton was one of the leading evolutionary biologists of our time. His theory of inclusive fitness ('kin selection') [...]

It is suggested by Rutherford and Lindquist that the heat-shock protein Hsp90 fosters the accumulation of hidden variants that may be exposed by environmental challenges, and fixed by selection. This explicit molecular mechanism helps in the process of evolutionary change. Such interpretation appears to require evolution of properties that anticipate future needs, although selection lacks foresight. An obvious function of Hsp90 is to stop abnormalities of the type that appear when it is compromised. Natural selection is the ultimate source of all purposeful design, and discussion on the evolutionary process should observe the distinction between function or purpose, and effect or consequence.

Coalescent theory provides an elegant and powerful method for understanding the shape of gene genealogies and resulting patterns of genetic diversity. However, the coalescent does not naturally accommodate the effects of heritable variation in fitness. Although some methods are available for studying the effects of strong selection (Ns ≫ 1), few tools beyond forward simulation are available for quantifying the impact of weak selection at many sites. Here, we introduce a continuous-state coalescent capable of accurately describing the distortions to genealogies caused by moderate to weak natural selection affecting many linked sites. We calculate approximately the full distribution of pairwise coalescent times, the lengths of coalescent intervals, and the time to the most recent common ancestor of a sample. Weak selection (Ns ≈ 1) is found to substantially decrease the tree depth, primarily through a shortening of the lengths of the basal coalescent intervals. Additionally, we demonstrate that only two parameters, population size and the variance of the distribution describing fitness heritability, are sufficient to describe most changes. [ABSTRACT FROM PUBLISHER]

Examines the relationship between spider size and the silk volume and total stickiness of webs produced by four orb-weaving species and four species that spin simpler webs. Web measurements; Thread diameters; Cribellar thread stickiness.

The article discusses an approach for determining the increase in whale calf mortality rates at Península Valdés, Argentina after 2003. It is noted that the efficiency of the Southern Right Whale Health Monitoring Program (SRWHMP) cannot be determined due to the lack of a relevant estimation method. One estimation approach suggested by the author is to assume that a historic increase in calf mortality rates occurred in the first four years of the stranding project.

Profiles biologist William Donald Hamilton. Founding of the theory of inclusive fitness or 'kin selection'; Contributions in the improvement of the concept of social behavior; Works; Employment history; Major contribution to the evolutionary theory; Death.