Season 5 Episode 5: Hot Orcas and Superfluous Males

In this episode Sarah, Mark and James continue their discussion of the book Bitch by Lucy Cooke where they explore menopause in humans and non-human animals and discuss those animals that have forwent males when they reproduce. The first conversation explored how orcas are an unusual mammal in that the males do not disperse from their mother's pod, but instead they retain a close relationship with their mothers. The ultimate momma's boy. 

Sarah discussed the various hypothesis for why women would actually go through menopause, and why it is an evolutionary puzzle. One of the hypothesis that Sarah thought had traction was the fact that human women at birth reduce their one million oocytes to about 300,000 at birth, and the number and quality of eggs continue to decline with age. 

The oocytes of a human female in stasis awaiting the monthly opportunity to develop into a fertile egg.

We discussed why it is the female orca that experiences menopause and not the males. We finished the podcast discussing single sex albatross pairs who successfully rear offspring every year. James discussed seeing these birds raising their single offspring in the yards of a suburban neighborhood. Humans have encroached on much of the historical nesting sites of the albatross on the Hawaiian islands but Nevertheless, she persisted. Here is a picture of a baby albatross James took on Kauai where it is manipulating its parents by maintaining the baby downy feathers on its head while the adult feathers are on the rest of the body. 

We finished the podcast discussing the parthenogenic Mourning geckos that have colonized many of the islands of the Pacific since they can reproduce asexually. Virgin births have been observed in many chordates except in mammals. We discussed why that may be.

A Mourning Gecko James photographed when doing field work in Kauai.

Opening and closing music is "May" by Jared C. Balogh.

Interlude music Confessions by Sudan Archives

 

Season 5 Episode 4: Ken the Naked Mole Rat

 

In this episode Sarah, Mark, and James continue their coverage Bitch by Lucy Cooke. We discussed systems where female aggression was common and the subjugation of other females and males was done by "alpha" females.  We were surprised to learn how murderous and violent naked mole rats and sweet little meercats could be. 

Photo from Akron Zoo

Naked mole rats are eusocial mammals where a dominant female is the sole reproducer in the colony and others help rear the young. Here is a photo of a queen rat with her newborn pubs and other females assisting in their care. Do not be fooled by the serene nature of this image, those helper females are violently coerced into their roles.

Photo from https://lsc.org/news-and-social/news/our-naked-mole-rats-had-babiesagain

Meercats are also a fossorial social mammal that is ruled ruthlessly by the dominant female. The play of meercats often mimics fighting, which is always a constant possibility in their tight knit clan.

The second half of the discussion focused on female dominant systems that rely more on alliances and social bonding to create group coherence. Ring tailed lemurs and bonobo chimpanzees were the classic system we discussed. At the end we tried to make sense of how ecology, physiology, and culture might be influencing a social system being matriarchal or patriarchal. Sarah noted that the males in these female dominant social systems reminded her of Ken in the movie Barbie. 

Opening and closing music is "May" by Jared C. Balogh.

Interlude music My Humps by the Black Eyed Peas

  

 

Seson 5 Episode 3 - Variable Vaginas and Punchable Penises

We continue our discussion of Lucy Cooke's book entitled Bitch: On the female of the species focusing on chapters 5 & 6 which covered variation in female genitalia, the evolution of the human penis,  and maternal care. We spent some time talking about the baculum, a bone that is found in the penis of many mammals, but not in humans. Sarah described how intricately shaped the baculum of squirrels can be, as evident in the image below. 

From Bacula of North American Mammals by W. H. Burt, 1960

Sarah also discussed a novel hypothesis presented by Jakovlic'  that proposes and explanation for the loss of human baculum through male-male aggression. James wondered why human copulation lasts so long? What is the point of all that thrusting for minutes on end?  We explored a couple of hypothesis that have been proposed to explain the exuberant level of pelvic thrusting typical in human copulation. 

James encouraged our listeners to look at the NSFW artwork of Jamie McCartney, a sculpture and photographer who has created a large portfolio of casts of penises and vaginas, and other secondary sexual characteristics, which clearly represent the variability in human genitalia. 

The second part of the podcast explored the myth of maternal care and how opposing neurological process can explain aggression towards babies or care and protection of babies. We explored how these process could help explain post-partum depression and how the modern medical process in child birth may interfere with the evolved bonding process that requires specific tactile, auditory, and olfactory cues shared between the mother and newborn. 

Opening and closing music is "May" by Jared C. Balogh.

Interlude music was Detachable Penis from King Missile. 

 

Season 5 Episode 2: Your O face

 

In this episode we continue our conversation based upon Chapters 3 & 4 of Lucy Cooke's book Bitch: on the female of the species. We started off the conversation doing a deep dive on the famous Bateman experiment that purported to reveal 3 principles concerning variation in male and female reproductive success and how those differences drive sexual selection. After reviewing the experiments and what they were reported to show, Sarah then discussed some more recent papers that closely re-analyzed the original 1948 experiment and how that revealed critical flaws and biases in the study which weakens the strength of its conclusion.   We were left with thinking it is more Bateman Hypothesis than Bateman's Principles. 

Once we established that it is not correct to characterize females as being coy and unwilling to mate more than once, we explored the reasons why females would exhibit a level of promiscuity that rivals that expected from males. We discussed the orgasm as a feature in sexual activity and how scientists have tried to characterize this physiological response in other non-human primates. 

Image of O face adapted from drawing in Bitch from Chevalier-Skolnikoff's research.

We had a spirited conversation about the evolution of the female orgasm and how it might influence females seeking multiple mates. 

We ended the podcast with a discussion of sexual cannibalism. We explored the reasons why, in some species of spiders, the males are so much smaller than the adult females which facilitates her eating the male. Although killing and eating a potential mate seems maladaptive, we discussed the various reasons why it may be adaptive for the female and for the male to kill or be killed. 

Post mating cannibalism in a web building spider. Image from Schneider 2014 

The opening theme to Discovering Darwin is "May" by Jared C. Balogh. http://freemusicarchive.org/music/Balogh/Revitalized_Eyes/MAY


Interlude music
Girls Just Want To Have Fun. Song by Cyndi Lauper
Maneater. Song by Hall & Oats

Season 5 Episode 1-Incubated in misogyny

We have returned from a long hiatus to discuss a wonderful book entitled Bitch: On the Female of the Species by Lucy Cooke. Sarah asked James and Mark to read this book that gives an updated look at Darwin's original model of sexual selection, a topic we covered extensively in Season 4. In this episode we cover the introduction and first 2 chapters of the book.

In our conversation about the book, we discuss how Darwin's stereotypical, and simplistic. views of male and female roles in mating and reproduction have persisted 150 years later. As Sarah says, we are still suffering from the hangover Darwin's misogyny. Chapter one of the book does a great job challenging the simplistic notion of what "is a female?", and we explore that topic in detail. Mark was enamored with the existence of gynandromorphs (gyn=female, andro=male, morph=form), organisms that exhibit both male and female phenotypic structures. This led us to discuss the difference between sex and gender and why the simplistic view, often exposed in popular culture of late, of there being only 2 sexes, is incorrect and ignores actual biology. 

Image taken from https://www.eriebirdobservatory.org/ebo-blog/2021/2/21/a-second-bilateral-gynandromorph-northern-cardinal-in-northwest-pennsylvania

We also discuss how stereotypical gender roles influence how biologists interpret the behaviors they observed which often leads to misunderstanding and faulty interpretations. We encourage our listeners to read along with us, as we plan to discuss Chapters 3 & 4 next episode. 

Lucy Cooke (Photo: David Dunkerley)

Here is another example of gynandromorphs, but in butterflies.

Image from https://www.earth.com/news/gynandromorphs-half-male-half-female/

The opening theme to Discovering Darwin is "May" by Jared C. Balogh. http://freemusicarchive.org/music/Balogh/Revitalized_Eyes/MAY     

Interlude music

Bitch Song by Meredith Brooks

Sage Grouse calls were from Greater Sage-grouse strut display 
https://www.youtube.com/watch?v=m0M8pZnNlnI

Season 4 Episode 10: Darwin is WRONG! Click here to learn more

In this final episode of Season 4, Mark, Sarah, and James finally critiqued Darwin's analysis of secondary sexual characteristics in humans and his clumsy attempt to apply his model of sexual selection in explaining the diversity of forms in what Darwin called "races" and we call geographically distinct phenotypes (GDPs). We found that Chapters 19 & 20 of Descent of Man distilled and concentrated Darwin's most ethnocentric and sexist observations and pseudo-scientific explanations concerning the differences between the sexes and GDPs. 

Image from Wilson, Miller, and Crouse (2017)

Sarah made the argument that human sexual dimorphism, differences in size and body form of males versus females, is the smallest of all seen in extant primates. Sarah questioned why Darwin tried to assign those slight differences to sexual selection. James made the argument that there are two categories of traits that Darwin was discussing. James referred to the physical traits, like hair color, skin color, height, facial shape, etc. are intrinsic traits you inherit genetically. Humans also exhibit extrinsic traits, hair styles, piercings, tattoos, clothing, etc. which you inherit culturally. 

Mark explained the complexity of beauty and why attraction and beauty are two different issues. We explored how specific standards of beauty are locally determined and how how diverse they can be across the globe. Both James and Sarah independently concluded that Darwin's model of sexual selection was not sufficient in explaining the creation of the great diversity of human forms seen between the geographically distinct phenotypes around the world. Sarah invoked founder effects and genetic drift, non selective processes, in creating genetically distinct populations that were then acted upon by local selective pressures, both from the environment and within the social group. It is through those processes Sarah thought created the geographically distinct phenotypes, and not through sexual selection. James agreed and thought that selection at the group level, where everyone in the social group, enforced phenotypic norms on others through infanticide and cultural practices of shunning or killing undesirables created the diversity of forms seen among the GDPs.  Sarah and James' models do not require the extreme level of sexual selection and polygyny required in Darwin's model to shift the phenotype of the entire population. Also, the social cohesion model of selection can allow for rapid shifts in the phenotype as the entire social group enforces the phenotypic norms instead of just the mating male and who he selects to mate with. 

The opening theme to Discovering Darwin is "May" by Jared C. Balogh. http://freemusicarchive.org/music/Balogh/Revitalized_Eyes/MAY     

Interlude music

You are so beautiful - Joe Cocker (1974)
I'm too sexy - Right Said Fred (1992)

    

 

Season 4 Episode 9: Love Antics and Conspicuous Ornamentations

 

After a long COVID induced hiatus, we have returned to tackle the meaty middle of Charles Darwin's magnum opus The Descent of Man. It was actually most of Volume 2, three hundred and nineteen pages of anecdotes, observations, wild conjecture, and chuck'splaining his crazy system of inheritance. The dense plodding Victorian prose was diluted, a bit, by the amazing woodcut prints of beetles, fish, lizards, exotic birds whose feathers were stolen by Victorian women, and ornamented antelopes and other mammals. 

Human female adorned with decorative feathers stolen from birds

Mark covered the fish, amphibians, and reptiles, since James forgot to assign the invertebrates, we did not discuss the myriad beetle examples Darwin discussed. However, Mark was impressed with the ways in which fish, during the breeding season, become so brightly colored. We mentioned a local fish, the male rainbow darter, which is quite striking during the spring breeding season. Mark was surprised to learn that there is no such thing as a fish and Sarah encouraged him to read Why Fish Don't Exist: A Story of Loss, Love, and the Hidden Order of Life – by Lulu Miller

Rainbow darter male

Mark expressed his disappointment in the lack of sexual dimorphism in snakes, an animal group he has an inordinate fondness for. Although we did not discuss the invertebrates, James brought up the interesting sex determination system in slipper shell molluscs (pictured below) and how the top individual becomes the male, and all the ones below shift to be female. 

James tackled the immense bird section and offered a variety of hypothesis why the males of a species may look different than the females, in addition to Darwin's model of sexual selection and female choice. We also discussed the unique sex chromosome system in birds and how that is opposite of what we see in mammals and how some scientists believe it helped accelerate and magnify sexual dimorphism in birds. 

Fig. 47. Paradisea Papuana (T. W. Wood).

Sarah covered sexual dimorphism in mammals and noted that Darwin believed most of that dimorphism was created through male-male battles for access to females and less about female choice. We had a lengthy discussion of antlers and horns and how they sometimes show up in both sexes but often is only found on the males. Sarah also discuss African lion manes and how they vary in shape and color where the darkest mane is the one most successful in fights and securing mates but there are costs with having the mane. 

A lion with a very dark mane

We also discussed the odd stotting behavior of some ungulates, as shown in the gif below. 

The opening theme to Discovering Darwin is "May" by Jared C. Balogh. http://freemusicarchive.org/music/Balogh/Revitalized_Eyes/MAY

Interlude music

Fat Caps by Jason Shaw

https://freemusicarchive.org/music/Jason_Shaw/Audionautix_Tech_Urban_Dance/TU-FatCaps/

Love Cats by the Cure