Parallel Evolution of Auditory Genes for Echolocation in Bats and Toothed Whales

The ability of bats and toothed whales to echolocate is a remarkable case of convergent evolution. Previous genetic studies have documented parallel evolution of nucleotide sequences in Prestin and KCNQ4, both of which are associated with voltage motility during the cochlear amplification of signals. Echolocation involves complex mechanisms. The most important factors include cochlear amplification, nerve transmission, and signal re-coding. Herein, we screen three genes that play different roles in this auditory system. Cadherin 23 (Cdh23) and its ligand, protocadherin 15 (Pcdh15), are essential for bundling motility in the sensory hair. Otoferlin (Otof) responds to nerve signal transmission in the auditory inner hair cell. Signals of parallel evolution occur in all three genes in the three groups of echolocators—two groups of bats (Yangochiroptera and Rhinolophoidea) plus the dolphin. Significant signals of positive selection also occur in Cdh23 in the Rhinolophoidea and dolphin, and Pcdh15 in Yangochiroptera. In addition, adult echolocating bats have higher levels of Otof expression in the auditory cortex than do their embryos and non-echolocation bats. Cdh23 and Pcdh15 encode the upper and lower parts of tip-links, and both genes show signals of convergent evolution and positive selection in echolocators, implying that they may co-evolve to optimize cochlear amplification. Convergent evolution and expression patterns of Otof suggest the potential role of nerve and brain in echolocation. Our synthesis of gene sequence and gene expression analyses reveals that positive selection, parallel evolution, and perhaps co-evolution and gene expression affect multiple hearing genes that play different roles in audition, including voltage and bundle motility in cochlear amplification, nerve transmission, and brain function

Explaining Seemingly Paradoxical Consumer Experiences: Conjoining Weekly Road Rage and Church Attendance

© 2013, Springer Science+Business Media New York.The purposes of the current study are threefold: Provide evidence that an extreme paradoxical group exists—people frequently attending church and exhibiting road rage, profile this group, and frame possible explanations for the seemingly paradoxical behaviors. This study employs data from a national (USA) lifestyle survey conducted by Market Facts with 3,350 American respondents. The major questions asked about church participation and road-rage behavior (“giving a finger” and “flashing headlights”). Nomologically, relevant activities include 3 items for church goers and 3 items for road-rage givers. Additionally, 14 items profiled the lifestyles of the unique paradoxical behavior segment. Utilizing cross-tabulation tables, property space analyses identify the double extreme (XX) group (18 people) and other 6 groups with a significant chi-square test, confirming the extreme group exists. Analyses of variance test results show that comparing nomologically relevant activities among the seven groups is all statistically significant, indicating the nomological validity is met. Overall, the XX group tends to have more males, be younger, and have a higher proportion of people working in sales. The profile of lifestyle analyses shows the XX group members have both high ambitions and expectations, might be very frustrated individuals, and equip with the adventurous and masculine traits related to aggression. The XX behavior group’s demographic and psychographic characteristics portray similar lifestyles that differ from other groups. Case-based analyses provide further contextual information of nuances to XX segment individuals. The limited energy theory, the Eagleman’s theory of unconscious mind, and justification theory help to explain why people conjointly go to church and commit road rage. Addressing chronic paradoxical behaviors provides implications for social de-marketing to reduce aggressive anti-social behavior such as road rage. Frequent church attendance may help make people more sensitive to their wrongdoings and gradually revise the anti-social behavior