Instead of the human larynx having increased complexity, it has actually simplified relative to other primates, allowing for clearer sound production with less aural chaos

Evolutionary loss of complexity in human vocal anatomy as an adaptation for speech. Takeshi Nishimura et al. Science, Aug 11 2022, Vol 377, Issue 6607, pp. 760-763. DOI: 10.1126/science.abm1574

When less is more in the evolution of language

Complexity from simplification

Human speech and language are highly complex, consisting of a large number of sounds. The human phonal apparatus, the larynx, has acquired the capability to create a wider array of sounds, even though previous work has revealed many similarities between our larynx and those in other primates. Looking across a large number of primates, Nishimura et al. used a combination of anatomical, phonal, and modeling approaches to characterize sound production in the larynx (see the Perspective by Gouzoules). They found that instead of the human larynx having increased complexity, it has actually simplified relative to other primates, allowing for clearer sound production with less aural chaos. —SNV

Abstract: Human speech production obeys the same acoustic principles as vocal production in other animals but has distinctive features: A stable vocal source is filtered by rapidly changing formant frequencies. To understand speech evolution, we examined a wide range of primates, combining observations of phonation with mathematical modeling. We found that source stability relies upon simplifications in laryngeal anatomy, specifically the loss of air sacs and vocal membranes. We conclude that the evolutionary loss of vocal membranes allows human speech to mostly avoid the spontaneous nonlinear phenomena and acoustic chaos common in other primate vocalizations. This loss allows our larynx to produce stable, harmonic-rich phonation, ideally highlighting formant changes that convey most phonetic information. Paradoxically, the increased complexity of human spoken language thus followed simplification of our laryngeal anatomy.

Why are males not doing these environmental behaviors?: exploring males’ psychological barriers to environmental action

Why are males not doing these environmental behaviors?: exploring males’ psychological barriers to environmental action. Jessica E. Desrochers & John M. Zelenski. Current Psychology, Aug 13 2022. https://rd.springer.com/article/10.1007/s12144-022-03587-w

Abstract: Previous research has reported that females are more likely than males to do pro-environmental behaviors. This research focused on understanding this relationship by exploring individual difference characteristics that may explain the sex difference, specifically traits and psychological barriers to pro-environmental action. Two studies (N = 246 and N = 357) confirm that males were less likely to report doing pro-environmental behaviors; males also reported more of Gifford’s (2011) Dragons of Inaction Psychological Barriers (DIP-Barriers) to pro-environmental action than females. Broad traits predicted pro-environmental attitudes and behaviors similar to past research, but they did not account for the sex difference. In addition, we suggest a new psychological barrier for males: perceptions of femininity may dissuade males from some pro-environmental behaviors. Results provide preliminary support for this idea and complement previous suggestions that environmentalism is perceived as more feminine. We discuss ways that future research can build on these suggestions with the ultimate goal of more effectively promoting environmentalism to males.