Jul 14, 2017

Scientists find neurons that make an alpha male

Rama / Wikipedia

A small group of neurons in the brains of mice may control whether males are aggressive or submissive in encounters with other males, according to new research.

Why it matters: Social dominance exhibited by certain males in groups — the basic definition of alpha males — is an important evolutionary trait in nearly every animal species (including, to a limited extent, humans). Male "winners" in aggressive contests or situations with peers accrue benefits, provided they keep winning.

Scientists have known for some time that a part of the brain (the dorsomedial pre-frontal cortex) is involved in regulating social dominance traits in males. What they didn't know was how it worked. In this new study, scientists tested the mechanism by pitting mice against each other, and then activating the neurons (or shutting them down) during those "showdowns" to see how they reacted.

What they found: Mice with the fired-up neurons in that part of the brain acted more like alpha males (pushing back, fighting, resisting, etc.), while those that had those neurons suppressed were more passive and less inclined toward social dominance behavior that characterizes "winning."

Go deeper

World coronavirus updates

Data: The Center for Systems Science and Engineering at Johns Hopkins; Map: Axios Visuals

There are no COVID-19 patients in hospital in New Zealand, which reported just 21 active cases. A top NZ health official said Tuesday he's "confident we have broken the chain of domestic transmission."

By the numbers: Almost 5.5 million people have tested positive for the novel coronavirus as of Tuesday, and more than 2.2 million have recovered. The U.S. has reported the most cases in the world (over 1.6 million from 14.9 million tests).

U.S. coronavirus updates

Data: The Center for Systems Science and Engineering at Johns Hopkins; Map: Andrew Witherspoon/Axios. This graphic includes "probable deaths" that New York City began reporting on April 14.

Coronavirus antibody tests are still relatively unreliable, and it's unclear if people who get the virus are immune to getting it again, the Centers for Disease Control and Prevention cautioned on Tuesday.

By the numbers: More than 98,900 people have died from COVID-19 and over 1.6 million have tested positive in the U.S. Over 384,900 Americans have recovered and more than 14.9 million tests have been conducted.

Coronavirus dashboard

Illustration: Aïda Amer/Axios

  1. Global: Total confirmed cases as of 9:30 p.m. ET: 5,588,299 — Total deaths: 350,417 — Total recoveries — 2,286,827Map.
  2. U.S.: Total confirmed cases as of 9:30 p.m. ET: 1,680,625 — Total deaths: 98,902 — Total recoveries: 384,902 — Total tested: 14,907,041Map.
  3. Federal response: DOJ investigates meatpacking industry over soaring beef pricesMike Pence's press secretary returns to work.
  4. Congress: House Republicans to sue Nancy Pelosi in effort to block proxy voting.
  5. Business: How the new workplace could leave parents behind.
  6. Tech: Twitter fact-checks Trump's tweets about mail-in voting for first timeGoogle to open offices July 6 for 10% of workers.
  7. Public health: Coronavirus antibodies could give "short-term immunity," CDC says, but more data is neededCDC releases guidance on when you can be around others after contracting the virus.
  8. What should I do? When you can be around others after contracting the coronavirus — Traveling, asthma, dishes, disinfectants and being contagiousMasks, lending books and self-isolatingExercise, laundry, what counts as soap — Pets, moving and personal healthAnswers about the virus from Axios expertsWhat to know about social distancingHow to minimize your risk.
  9. Other resources: CDC on how to avoid the virus, what to do if you get it, the right mask to wear.

Subscribe to Mike Allen's Axios AM to follow our coronavirus coverage each morning from your inbox.

Updated 1 hour ago - Politics & Policy