Skip to main content
Advertisement

Main menu

  • Home
  • Articles
    • Accepted manuscripts
    • Issue in progress
    • Latest complete issue
    • Issue archive
    • Archive by article type
    • Special issues
    • Subject collections
    • Interviews
    • Sign up for alerts
  • About us
    • About JEB
    • Editors and Board
    • Editor biographies
    • Travelling Fellowships
    • Grants and funding
    • Journal Meetings
    • Workshops
    • The Company of Biologists
    • Journal news
  • For authors
    • Submit a manuscript
    • Aims and scope
    • Presubmission enquiries
    • Article types
    • Manuscript preparation
    • Cover suggestions
    • Editorial process
    • Promoting your paper
    • Open Access
    • Outstanding paper prize
    • Biology Open transfer
  • Journal info
    • Journal policies
    • Rights and permissions
    • Media policies
    • Reviewer guide
    • Sign up for alerts
  • Contacts
    • Contact JEB
    • Subscriptions
    • Advertising
    • Feedback
  • COB
    • About The Company of Biologists
    • Development
    • Journal of Cell Science
    • Journal of Experimental Biology
    • Disease Models & Mechanisms
    • Biology Open

User menu

  • Log in

Search

  • Advanced search
Journal of Experimental Biology
  • COB
    • About The Company of Biologists
    • Development
    • Journal of Cell Science
    • Journal of Experimental Biology
    • Disease Models & Mechanisms
    • Biology Open

supporting biologistsinspiring biology

Journal of Experimental Biology

  • Log in
Advanced search

RSS  Twitter  Facebook  YouTube  

  • Home
  • Articles
    • Accepted manuscripts
    • Issue in progress
    • Latest complete issue
    • Issue archive
    • Archive by article type
    • Special issues
    • Subject collections
    • Interviews
    • Sign up for alerts
  • About us
    • About JEB
    • Editors and Board
    • Editor biographies
    • Travelling Fellowships
    • Grants and funding
    • Journal Meetings
    • Workshops
    • The Company of Biologists
    • Journal news
  • For authors
    • Submit a manuscript
    • Aims and scope
    • Presubmission enquiries
    • Article types
    • Manuscript preparation
    • Cover suggestions
    • Editorial process
    • Promoting your paper
    • Open Access
    • Outstanding paper prize
    • Biology Open transfer
  • Journal info
    • Journal policies
    • Rights and permissions
    • Media policies
    • Reviewer guide
    • Sign up for alerts
  • Contacts
    • Contact JEB
    • Subscriptions
    • Advertising
    • Feedback
INSIDE JEB
Evolution built men to pack a punch
Kathryn Knight
Journal of Experimental Biology 2020 223: jeb221135 doi: 10.1242/jeb.221135 Published 3 February 2020
Kathryn Knight
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • For correspondence: kathryn.knight@biologists.com
  • Article
  • Figures & tables
  • Info & metrics
  • PDF
Loading
Figure1
  • Download figure
  • Open in new tab
  • Download powerpoint

A volunteer cranking the flywheel to simulate throwing a punch. Photo credit: Jeremy Morris.

The differences between males and females can be extreme. Tiny triplewart seadevil males simply fuse themselves for life to their relatively large female partners while female rusty tussock moths are almost immobile egg carriers for their more elaborate males. Although the differences between male and female humans are far less dramatic, men can have up to 90% more upper body strength than women. ‘[The] difference between males and females often reveals how evolution has shaped the bodies of males and females in different ways’, says Jeremy Morris from Wofford College, USA, who was curious to find out why men are so much more powerful than women. The possibility that male hand-to-hand combat was a driving force in human evolution has long intrigued Morris's thesis advisor, David Carrier at the University of Utah, USA, so Morris decided to check out whether coming to blows could have driven men to build up.

But Morris, Carrier, Jenna Link and James Martin, also from the University of Utah, had to come up with an alternative way of testing how much power people pack in punches. ‘People that are not trained in martial arts are hesitant to punch a punching bag with much force because there is a risk of injury’, says Morris. However, after putting their heads together the team came up with the idea of sitting volunteers down and asking them to power their arms forward by simply cranking a flywheel. ‘The advantage of using arm cranking … is that we can get maximum performance from people that have little or no experience punching’, says Morris.

Recruiting almost 40 reasonably fit adult volunteers from friends and colleagues around the campus, Morris and Link asked them to warm up gently before driving the crank wheel as hard as possible over the top third of a full rotation to simulate a punching action. ‘We encouraged the participants, yelling “Go, go, go! Come on!” the same way that a physical trainer would at a gym to get the maximum performance’, recalls Morris. Calculating the amount of power each participant threw into spinning the heavy flywheel, the chaps came out streets ahead of the women, packing almost three times more power on average into their wheel spins (282 W) than the females (108 W). However, when the team tested how much effort the adults could put into pulling the wheel in reverse, the differences were less pronounced; the men only just doubled the amount of power exerted by the women. In addition, when the team compared how much more force the male volunteers were able to invest in overarm throwing – an alternative theory for the differences between the physical builds of men and women – the men only invested twice as much power as the women.

‘The results of this study support the hypothesis that evolution has selected for physical traits in males that make them better at inflicting damage by punching with the fist’, says Morris. And he is keen to find out how hard male and female trained athletes can throw a punch, to answer an important question: is punching the physical activity with the greatest disparity between men and women?

References

    1. Morris, J. S.,
    2. Link, J.,
    3. Martin, J. C. and
    4. Carrier, D. R.
    (2020). Sexual dimorphism in human arm power and force: implications for sexual selection on fighting ability. J. Exp. Biol. 223, jeb212365. doi:10.1242/jeb.212365
    OpenUrlAbstract/FREE Full Text
Previous ArticleNext Article
Back to top
Previous ArticleNext Article

This Issue

 Download PDF

Email

Thank you for your interest in spreading the word on Journal of Experimental Biology.

NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address.

Enter multiple addresses on separate lines or separate them with commas.
Evolution built men to pack a punch
(Your Name) has sent you a message from Journal of Experimental Biology
(Your Name) thought you would like to see the Journal of Experimental Biology web site.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Share
INSIDE JEB
Evolution built men to pack a punch
Kathryn Knight
Journal of Experimental Biology 2020 223: jeb221135 doi: 10.1242/jeb.221135 Published 3 February 2020
del.icio.us logo Digg logo Reddit logo Twitter logo CiteULike logo Facebook logo Google logo Mendeley logo
Citation Tools
INSIDE JEB
Evolution built men to pack a punch
Kathryn Knight
Journal of Experimental Biology 2020 223: jeb221135 doi: 10.1242/jeb.221135 Published 3 February 2020

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero
Alerts

Please log in to add an alert for this article.

Sign in to email alerts with your email address

Article navigation

  • Top
  • Article
    • References
  • Figures & tables
  • Info & metrics
  • PDF

Related articles

Cited by...

More in this TOC section

  • Making a difference: the role of comparative biology in tackling climate change
  • Lifestyle difference gives female yellow-billed hornbills the edge
  • High-voltage catfish immune to their own shocks
Show more INSIDE JEB

Similar articles

Other journals from The Company of Biologists

Development

Journal of Cell Science

Disease Models & Mechanisms

Biology Open

Advertisement

Welcome to JEB’s new Editor Monica Daley

We are pleased to welcome Monica Daley to JEB’s Editorial team. Monica has had a long association with JEB before taking up her new role, overseeing peer review of neuromuscular physiology, terrestrial biomechanics and integrative physiology of locomotion.


In the field with Robyn Hetem

Continuing our fieldwork series, Robyn Hetem reflects on working with species ranging from aardvark to zebra, and the impact COVID-19 has had on fieldwork.


Read & Publish participation continues to grow

“It is particularly encouraging for early career researchers, as it allows them to display their research globally without the need to find costs to cover the open access option.”

Professor Fernando Montealegre-Z (University of Lincoln) shares his experience of publishing Open Access as part of our growing Read & Publish initiative. We now have over 150 institutions in 15 countries and four library consortia taking part – find out more and view our full list of participating institutions.


Nocturnal reef residents have deep-sea-like eyes

Fanny de Busserolles and colleagues from The University of Queensland have discovered that the eyes of nocturnal reef fish have multibank retinas, layers of photoreceptors, similar to the eyes of deep-sea fish that live in dim light conditions.


Mechanisms underlying gut microbiota–host interactions in insects

In their Review, Konstantin Schmidt and Philipp Engel summarise recent findings about the mechanisms involved in gut colonisation and the provisioning of beneficial effects in gut microbiota–insect symbiosis.

Articles

  • Accepted manuscripts
  • Issue in progress
  • Latest complete issue
  • Issue archive
  • Archive by article type
  • Special issues
  • Subject collections
  • Interviews
  • Sign up for alerts

About us

  • About JEB
  • Editors and Board
  • Editor biographies
  • Travelling Fellowships
  • Grants and funding
  • Journal Meetings
  • Workshops
  • The Company of Biologists
  • Journal news

For Authors

  • Submit a manuscript
  • Aims and scope
  • Presubmission enquiries
  • Article types
  • Manuscript preparation
  • Cover suggestions
  • Editorial process
  • Promoting your paper
  • Open Access
  • Outstanding paper prize
  • Biology Open transfer

Journal Info

  • Journal policies
  • Rights and permissions
  • Media policies
  • Reviewer guide
  • Sign up for alerts

Contact

  • Contact JEB
  • Subscriptions
  • Advertising
  • Feedback

 Twitter   YouTube   LinkedIn

© 2021   The Company of Biologists Ltd   Registered Charity 277992