There is no \u27obstetrical dilemma\u27: Towards a braver medicine with fewer childbirth interventions

Humans give birth to big-brained babies through a bony birth canal that metamorphosed during the evolution of bipedalism; they have a tighter fit at birth between baby and bony birth canal than do our closest relatives the chimpanzees; and they are incapable of grasping onto caregivers as early as infant chimpanzees develop the skill. Since the mid-20th century, these observations and more have been linked together into the obstetrical dilemma (OD): human babies are helpless because they are born early to escape before they outgrow the mother\u27s pelvis, the expansion of which is prevented by natural selection for bipedalism. The OD continues to be a popular idea, often expressed as incontrovertible fact, but it no longer deserves its popularity. There are better explanations for gestation length, childbirth difficulty, and the developmental biology of newborns than mainly or only because of natural selection\u27s constraints on women\u27s hips. And humans are not born early either, as is widely assumed. This all-too-powerful human evolutionary narrative deserves our skeptical consideration. Bias from OD thinking is likely amplifying the perceived risk of cephalopelvic and fetopelvic disproportion during labor—contributing, even if slightly, to medicine\u27s underestimation of women\u27s bodies and over-implementation of childbirth interventions

Origin of the Genus \u3ci\u3eHomo\u3c/i\u3e

The origin of the genus Homo in Africa signals the beginning of the shift from increasingly bipedal apes to primitive, large-brained, stone tool-making, meat-eaters that traveled far and wide. This early part of the human genus is represented by three species: Homo habilis, Homo rudolfensis, and Homo erectus. H. habilis is known for retaining primitive features that link it to australopiths and for being the first stone tool makers. Little is known about H. rudolfensis except that it had a relatively large brain and large teeth compared to H. habilis and that it overlapped in time and space with other early Homo. Our understanding of the paleobiology and evolution of the larger-brained H. erectus is enhanced due to its rich fossil record. H. erectus was the first obligate, fully committed biped, and with a body adapted for modern striding locomotion, it was also the first in the human lineage to disperse outside of Africa. The early members of the genus Homo are the first to tip the scale from the more apish side of our evolutionary history toward the more human one

The Evolution of Difficult Childbirth and Helpless Hominin Infants

Because of the implications for behavioral, social, and cultural evolution, reconstructions of the evolutionary history of human parturition are driven by two main questions: First, when did childbirth become difficult? And second, does difficult childbirth have something to do with infant helplessness? Here we review the available evidence and consider answers to these questions. Although the definitive time frame remains unclear, childbirth may not have reached our present state of difficulty until fairly recently

Senior Recital: Madeline Dunsworth, Violin; Zhiyuan Gao, Piano; November 13, 2022

Kemp Recital HallNovember 13, 2022Sunday Afternoon1:30 p.m

Reverse electrodialysis systems comprising wafer and applications thereof

In one aspect, reverse electrodialysis systems are described herein having constructions operable to reduce membrane stack resistance, thereby requiring significantly less membrane surface area for meaningful electrical power generation. A reverse electrodialysis system described herein comprises an anode and cathode adjacent to a membrane stack, the membrane stack comprising alternating anion and cation exchange membranes defining diluate and concentrate ionic solution compartments, wherein an ion exchange medium is positioned in a diluate compartment