Summary: Marshall et al. (2013)

So called "irrational biases" have become increasingly popular in the scientific literature, being studied across the broad disciplines of biology, neuroscience and psychology. Irrational biases can describe those behaviours that may not necessarily maximize fitness, but that individuals behave in a manner suggesting that the probability of a positive, or negative, outcome is greater than it actually is. Overconfidence, optimism and pessimism are considered irrational biases. Marshall et al. (2013) suggest that functional explanations underlying irrational biases is necessary, but an understanding of the benefits of irrational biases (e.g. overestimation of the probability of success during a conflict, or better deception of others through increased self-deception) is lacking. They also suggest that close attention must be paid to the difference between outcome and cognitive biases, even though this can impose challenges (as cognitive biases are subjectively experienced by individuals). Marshall et al. (2013) suggest that "an evolutionary theory of cognitive bias might require a closer integration of function and mechanism".

Summary: Mahler et al. (2013)

 In 1944, G. G. Simpson proposed the concept of a macroevolutionary adaptive landscape. This concept suggests that there is a multivariate phenotype surface upon which species evolve up local
adaptive peaks, leading to diversification. However, Mahler et al. (2013) note that current landscape models generally rarely study adaptive divergence in large radiations. They studied Caribbean Anolis lizards and found that diversification on Simpsonian landscapes results in convergence on four different islands of entire faunas. These parallel radiations over large time scales highlight the process of adaptive diversification. Furthermore, this is suggestive that predictable evolutionary patterns may arise from adaptive landscapes. In addition, Mahler et al. (2013) propose that these adaptive peaks are evolutionary stable over time and that available geographic area may influence lineage ability to discover adaptive peaks.

Summary: Song et al. (2013)

Eyes are incredible light-sensing organs and understanding how these organs functions facilitates the development of cameras with similar engineering principles. The arthropods (which includes the insects) show a sophisticated class of eye system. The field of view is wide-angled, with low aberrations. There is high motion acuity and an infinite depth of field. Currently, planar sensor technologies and conventional optics are insufficient for designing cameras with the similar hemispherical, compound apposition layouts characteristic of the arthropod eye. Song et al. (2013) designed a camera inspired by the arthropod eye, with nearly full hemispherical shapes (160 degrees) and present the materials, mechanics and integration schemes. The camera surface replicates the ommatidia of the arthropod eye, being densely populated by approximately 180 imaging elements, comparable to the eyes of fire ants (Solenopsis fugax) and bark beetles (Hylastes nigrinus). They suggest that their general strategies in the design and mechanics of this camera are applicable to other compound eye devices, such as those inspired by other insects (refracting and neural superposition eyes) and crustaceans (reflecting superposition eyes).

Summary: Reed et al. (2013)

Environmental change is one of the primary concerns of the 21st century. It is known that environmental change alters natural selection patterns in nature, but the demographic costs of persistent directional selection in response to change has yet to be quantified. Reed et al. (2013) attempted to quantify such changes in a population of wild great tits Parus major in the Netherlands. They tested whether a climate-change induced phenological mismatch negatively affected this population, which is known to have altered laying dates in response to warmer springs. Warmer springs have exerted strong directional selection for earlier laying, however, this no longer coincides with seasonal food peak abundance. Interestingly, Reed et al. (2013) found that this mismatch does not appear to have influenced population growth. They suggest that fitness losses associated with the mismatch are counteracted by fitness gains associated with a relaxation of competition. Their results are important, as they suggest that populations may be more tolerable of climate change events and may not undergo immediate declines as originally suggested.

Summary: van Kleef et al. (2013)

Obesity and increased weight gain is of considerable interest worldwide, in part due to an increase in portion size of energy-rich foods. van Kleef et al. (2013) questioned whether smaller snack sizes could be as effective at decreasing hunger cravings as larger snack sizes. They presented 104 participants with one of three common snack foods (chocolate, apple pie, potato chips), as either a larger or smaller portion. They found that small portions appeared to satisfy the participants hunger and craving ratings in a similar manner to larger portions, however, the overall caloric intake was less (by about 103 calories). van Kleef et al. (2013) suggest that although consuming less, a small snack can result in equal satisfaction after consumption.