Thursday, May 14, 2020

New Theory on the Origin of Fatherhood

Humans differ from other primates in the types and amounts of care that males provide for their offspring. The precise timing of the emergence of human “fatherhood” is unknown, but a new theory proposes that it emerged from a need for partnership in response to changing ecological conditions, U.S. and French researchers report in Proceedings of the National Academy of Sciences.

"Changes in the physical world—climate and habitat—from millions of years ago matter a great deal for what makes us human, including fatherhood,” said Boston College Professor of Economics Donald Cox, a co-author of the report.

Credit: Adam Jones from Kelowna, BC, Canada / Wikimedia Commons

The new theory was developed using tools of economists and knowledge of the economic and reproductive behavior of human foragers. The theory focuses on the benefits of a “fit” between exclusive partners that enabled the strengths of males and females to provide for one another and their offspring, according to Cox and colleagues from Chapman University, University of New Mexico, and the University of Toulouse in France.

Scientists have long tried to explain how human fatherhood emerged. Paternal care—those investments in offspring made by a biological father—is rare among mammals but widespread across modern human subsistence societies. Much of men’s parental investment consists of provisioning relatively helpless children with food for prolonged periods of time – for as long as two decades among modern hunter-gatherers. This is a sharp break with other great apes, whose observed mating systems do not encourage paternal provisioning.

That paternal provisioning arose in humans seems remarkable and puzzling and has revolved around a discussion about groups of males dubbed “Dads” and “Cads”.

With promiscuous mating, a would-be “Dad” who provides food for a mate and their joint offspring without seeking additional mates risks being outcompeted in terms of biological fitness by a “Cad”, who focuses only on promiscuous mating instead of investing in offspring. Such a competitive disadvantage creates a formidable barrier for Dads to emerge when Cads abound.

An oft-invoked explanation for the evolution of paternal provisioning in humans is that ancestral females started mating preferentially with males who provided them with food, in exchange for female sexual fidelity. This explanation is insufficient for several reasons, the researchers write.

Instead, the team of anthropologists and economists argues that ecological change would have sufficed to trigger the spread of Dads, even in the face of female sexual infidelity, according to the report, “Paternal provisioning results from ecological change.”

The key force in the theory of paternal provisioning is complementarities – in essence the cooperation between females and males, as well as between males. Complementarities are synergistic effects that increase per-capita benefits, which may arise from dividing labor and/or pooling resources. The path to complementarities began roughly five to eight million years ago, with a gradual drying in Africa, and a progressively greater need to rely on nutritious, diverse, spatially dispersed and relatively hard-to-obtain foods, including animal products.

In response to ecological change ancestral hominins adapted in various ways, including efficient bipedal locomotion, dietary flexibility, and an ability to thrive in diverse environments, facilitated by tool use. Complementarities between males and females would have resulted from the nutrients that each sex specialized in acquiring: protein and fat acquired by males paired well with carbohydrates acquired by females. Complementarities between males would have resulted from higher returns from hunting in groups instead of in isolation, and from food sharing to lower starvation risk. Dietary reliance on animal products is thus a key feature underlying these complementarities between and within sexes.

These complementarities would have led to a substantial increase in the impact of food provided by a Dad on the survival of his mate’s offspring.

Using evolutionary game theory, in the tradition of pioneering mathematician and geneticist John Maynard Smith, the authors show that this impact can lead Dads to gain a fitness advantage over Cads, although Cads may still co-exist with Dads under certain conditions. If sons inherit their biological father’s traits, then over time Dads will increase in number in a population. Theoretically connecting the evolution of paternal provisioning to ecological change allows the authors to make novel predictions about the paleontological and archeological record.

“Paternal provisioning results from ecological change," is published in Proceedings of the National Academy of Sciences | DOI: 10.1073/pnas.1917166117.




Contacts and sources:
Ed Hayward
Boston College


Publication: Paternal provisioning results from ecological change. Ingela Alger, Paul L. Hooper, Donald Cox, Jonathan Stieglitz, Hillard S. Kaplan. Proceedings of the National Academy of Sciences, 2020; 201917166 DOI: 10.1073/pnas.1917166117

4 comments:

  1. Online education writing services companies have come up with Online Education Assignment Help for education and teaching studies students in order for them to score straight A’s in their custom education research paper services.

    ReplyDelete
  2. God bless Dr. USELU for his marvelous work in my life, I was diagnosed of HERPES SIMPLEX VIRUS since 2018 and I was taking my medications, I wasn't satisfied i needed to get the HERPES out of my system, I searched about some possible cure for HERPES i saw a comment about Dr. USELU , how he cured HERPES with his herbal medicine, I contacted him and he guided me. I asked for solutions, he started the remedy for my health, he sent me the medicine within 3 days. I took the medicine as prescribed by him and 2weeks later i was cured from HERPES contact him via email (dr.uselucaregiver@gmail.com) once again thanks to you Dr. USELU cure the flowing virus, contact his email or add him on whatsapp (+2349019328641) cancer cure
    diabetes cure
    ringing ear
    herpes cure
    warts cure
    HPV cure
    HIV cure
    get your ex back
    pregnancy herbal medicine
    Hepatitis  

    ReplyDelete
  3. God bless Dr. USELU for his marvelous work in my life, I was diagnosed of HERPES SIMPLEX VIRUS since 2018 and I was taking my medications, I wasn't satisfied i needed to get the HERPES out of my system, I searched about some possible cure for HERPES i saw a comment about Dr. USELU , how he cured HERPES with his herbal medicine, I contacted him and he guided me. I asked for solutions, he started the remedy for my health, he sent me the medicine within 3 days. I took the medicine as prescribed by him and 2weeks later i was cured from HERPES contact him via email (dr.uselucaregiver@gmail.com) once again thanks to you Dr. USELU cure the flowing virus, contact his email or add him on whatsapp (+2348132015009) cancer cure
    diabetes cure
    ringing ear
    herpes cure
    warts cure
    HPV cure
    HIV cure
    get your ex back
    pregnancy herbal medicine
    Hepatitis

    ReplyDelete
  4. Investing online has been a main source of income,that's why knowledge plays a very important role in humanity,you don't need to over work yourself for money.All you need is the right information,and you could build your own wealth from the comfort of your home!Binary trading is dependent on timely signals,assets or controlled strategies which when mastered increases chance of winning up to 90%-100% with trading. It’s possible to earn $10,000 to $20,000 trading weekly-monthly,just file a complaint with  Robert,I had almost given up on everything about binary trading and ever getting my lost funds back,till i met with him,with his help now i have my lost funds back to my bank account and I can now trade successfully with his profitable strategies and software!! Email: Robertseaman939@gmail.com or Fb.me/investandmakemoney1 or  whatsApp: +44 7466 770724

    ReplyDelete