Summary: Heimann et al. (2009)

Veterinary practice, research and drug development has relied heavily on blood examination in laboratory animals. One of the common methods used for extracting blood from rodents is the retrobulbar venous plexus puncture. The advantage to this technique is the ability to harvest high volumes of blood, however, this technique can lead to extensive tissue damage, so much so that this method is only currently accepted if the procedure results in termination. Heimann et al. (2009) developed a novel puncture technique for rodents from the sublingual vein as an alternative to the retrobulbar venous plexus puncture technique. They found that large volumes of blood could be obtained using this method and that the method was suitable for rats, mice and hamsters. However, the sublingual vein in guinea pigs is not peripherally located, making this method impossible for these rodents. Heimann et al. (2009) also noted that sublingual venepuncture resulted in less tissue destruction in mice and, therefore, recommended this method over the retrobulbar venous plexus puncture technique.

Summary: Jozet-Alves et al. (2012)

Cerebral lateralization, defined as localization of function on either the right or left sides of the brain, was thought to be an exclusively human trait until recently. Lateralization is often perceived as asymmetries in motor behaviour, for example, a preference for using a particular hand, or turning in a particular direction. While lateralization studies in vertebrates are now common place, lateralization studies in invertebrates are more rare, although observations appear to parallel that seen in vertebrates. While lateralization in vertebrates can vary within an individual across its development, this was unknown in invertebrates. Jozet-Alves et al. (2012) examined lateralization during postembryonic development in juvenile cuttlefish Sepia officinalis, specifically focusing on when juveniles begin to show side-turning preferences. They found that juvenile cuttlefish progressively developed a left-turning bias between the ages of 3 and 45 days posthatch, but this was dependent on the presence of shelters. Jozet-Alves et al. (2012) suggest that this preference for turning left is a result of eye-use preference. This establishment of visual lateralization can provide juveniles with greater behavioural efficiency at dispersal, but increasing their ability to detect escape routes during hunting. It is possible that, by determining the role that the right visual field plays during prey-seeking in cuttlefish, this may provide evidence for homology for lateralization between vertebrates and invertebrates.

Summary: Hasegawa et al. (2013)

The sensory trap hypothesis proposes that courtship behaviour of males that mimic food-begging behaviour of offspring is a consequence of signal evolution. This results from males attempting to match stimuli that stimulate the female response in other contexts (for example, in parental care). As a result, females respond and male mating success increases. To humans, male courtship behaviour in many birds appears similar to food-begging behaviour of chicks. It is unclear, however, whether this behaviour does actually elicit a parental care response by females during courtship, indicative of a sensory trap. Hasegawa et al. (2013) studied barn swallows Hirundo rustica gutturalis and found that males make enticement calls that are structurally similar to nestling begging calls. When they played back these vocalizations to females during courtship, they observed females responding, even when nestlings were not present. Hasegawa et al. (2013) suggest that this represents a sensory trap, whereby a males mimic a signal which evokes a female response for an alternate behaviour (in this case, parental care).

Summary: Kuroki et al. (2013)

The interaction between transcription factor function and epigenetic status, which includes histone modification, defines developmental gene expression. Mammalian sex determination is influenced by various transcription factors, but the epigenetic regulation of this process is still unclear. Kuroki et al. (2013) studied sex reversal (male to female) in mice that lacked a particular enzyme - H3K9 demethylase Jmjd1a. They found that this enzyme regulates the expression of Sry gene, which is the mammalian Y chromosome sex-determining gene. Kuroki et al. (2013) showed that Jmdj1a directly controls Sry expression in a positive manner through its regulation of H3K9me2 marks. Their study demonstrates the important role that histone demethylation plays in mammalian sex determination.

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).