Summary: Byers & Dunn (2012)

 Male male competition and female mate choice are two aspects of sexual selection. In the case of male-male competition, the advantage of a competitor is largely determined by his fecundity, that is, the number of offspring he sires. Angus Bateman characterised this interaction in the form of a quantitative relationship known as the Bateman slope. This slope graphically depicts the relationship between a male's number of mates and the number of offspring produced. The potential for sexual selection is estimated from the slope of the line. Male mating success often relies on sexual dimorphism, and males with larger (heavier etc). traits are likely to achieve more matings. Generally, sexual dimorphism requires a positive Bateman slope. However, natural selection and random effects may also influence a male's ability to win mates. Byers & Dunn (2012) found a yearly positive Bateman slope for pronghorn Antilocapra americana over a decade, with no indication that random effects were skewing male mating success. They did find that there was variation between years due to fawn predation. Byers & Dunn (2012) suggest that environmental and/or extrinsic factors could limit sexual selection potential, but in general, the validity of a positive Bateman relationship is supported.

Summary: Corcoran et al. (2009)

 It has been hypothesized that the ultrasonic clicks made by some moth species in the presence of bats either warn bats of moth toxicity (aposematic signalling), startle bats that are not accustomed to sonic prey or are used to "jam" the bats echolocating signal. Tiger moths Bertholdia trigona are known to make ultrasonic clicks in response to the sonar clicks of some bats, such as big brown bats Eptesicus fuscus. Corcoran et al. (2009) studied which of these hypotheses is most likely for tiger moths using ultrasonic recording and high-speed infrared videography when moths interacted with bats. They found that tiger moths ultrasonic clicking jams big brown bat sonar. Sonar jamming has likely evolved in an evolutionary arms race between bats and insects.

Summary: Ortega-Jimenez & Dudley (2013)

The microstructure and ornamentation of spider webs influences their capture success. Furthermore, wind-induced vibrations may also influence capture success. Ortega-Jimenez & Dudley (2013) investigated whether positively electrostatically charged insects (honeybees Apis mellifera, green bottle flies Lucilia sericata, fruit flies Drosophila melanogaster, aphids Aphidoide) and water droplets influenced cross-spider Araneus diadematus web deformation as evidence has suggested that silk thread is attracted to electrostatically charged objects. Ortega-Jimenez & Dudley (2013) found that these electrostatically charged objects caused rapid deformation of spider thread, which they suggest could increase the risk of capture of flying prey.

Summary: Melichar & Robovský (2012)

Melichar & Robovský (2012) observed a novel defence group formation in captive golden takin Budorcas bedfordi, an ungulate that shares common features with the muskox Ovibos moschatus. A single day of occurrence of this behaviour was recorded in response to enclosure sharing with Chinese muntjacs Muntiacus reevesi. The formation was similar to that observed in wild muskox and rotated according to individual muntjac movement within the enclosure. The takin also emitted loud vocalisations and made several lunge attempts towards the muntjacs, although no direct contact was observed. This behaviour was exhibited multiple times on one day, but was not observed thereafter. Muntjacs actively avoided takin during this period, whereafter they entered the takin enclosure with limited interference. The takin thereafter ignored the muntjacs, although occasionally snorting was observed. Melichar & Robovský (2012) suggest that this behaviour has not be observed in wild takin. Due to its phylogenetic relationship with muskox, it is likely either that this behaviour evolved independently in the two groups, or occurred in a distant caprine ancestor.

Summary: Burgevin et al. (2013)

 The observation of same-sex sexual behaviour is common and taxonomically widespread. It is particularly observed in the insects, including the seed beetle Callosobruchus maculatus. While the focus of most research efforts have been on male-male same sex behaviour, some studies have started to investigate female-female same sex behaviour. The current theory behind male-male same sex behaviour is that the males accrue benefits associated with high mating rate, but that males are also poorly adept at discriminating between the sexes. This cannot explain female-female same behaviour as females do not typically mount males when mating. Burgevin et al. (2013) used a full-sib design and found that variation in male-male mount in the seed beetle explained a high proportion of the variation in female-female mounting behaviour, indicating an intersexual correlation. Their findings did not support that same-sex behaviour is related to activity or was costly for females. Burgevin et al. (2013) suggest that, at least for seed beetles, female-female same sex behaviour carries only a low cost and is maintained via selection on males in the population.