Oct 18, 2017

Dolphins' rich social lives may be tied to their bigger brains

Dolphins off coast of Zanzibar. Photos: cinoby / iStock

Whales and dolphins are already known to live in communities, play and communicate with one another using sophisticated sounds. A study published this week in Nature Ecology and Evolution reports those social behaviors are tied to their bigger brain size.

Why it matters: Human language and empathy — and in turn the formation of large, complex societies and cultures — are hypothesized to be the result of the brain expanding. Dolphins, whales and other cetaceans are far from humans on the evolutionary tree and live in very different environments. If this same coevolution of brains and social behavior and structures is true for them, it may help tease out what changes in brain size in humans are due to social behavior versus the environment.

The findings: Researchers looked at records of whale and dolphin behaviors — for example, caregiving, and learning from and playing with one another. They found cetaceans with larger brains live in more structured social groups and that brain size itself "predicts the breadth of social and cultural behaviors."

Go deeper: University of Manchester's Susanne Shultz, an author of the study, wrote in the Conversation about the work and open questions about species like the large-brained beaked whales that weren't studied because little is known about their behavior deep in the ocean.

Go deeper

Updated 2 hours ago - Politics & Policy

In photos: Protesters clash with police nationwide over George Floyd

Police officers grapple with protesters in Atlanta. Photo: Elijah Nouvelage/Getty Images

Police used tear gas, rubber bullets and pepper spray as the protests sparked by the killing of George Floyd spread nationwide on Friday evening.

The big picture: Police responded in force in cities ranging from Atlanta to Des Moines, Houston to Detroit, Milwaukee to D.C. and Denver to Louisville. In Los Angeles, police declared a stretch of downtown off limits, with Oakland issuing a similar warning.

Updated 3 hours ago - Politics & Policy

Supreme Court sides with California on coronavirus worship service rules

The Supreme Court has ruled 5-4, with Chief Justice John Roberts joining the court's liberal justices, to reject a challenge to California's pandemic restrictions on worship services.

Why it matters: This is a setback for those seeking to speed the reopening of houses of worship, including President Trump.

Updated 5 hours ago - Politics & Policy

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 10 p.m. ET: 5,923,432— Total deaths: 364,836 — Total recoveries — 2,493,434Map.
  2. U.S.: Total confirmed cases as of 10 p.m. ET: 1,745,930 — Total deaths: 102,808 — Total recoveries: 406,446 — Total tested: 16,099,515Map.
  3. Public health: Hydroxychloroquine prescription fills exploded in March —How the U.S. might distribute a vaccine.
  4. 2020: North Carolina asks RNC if convention will honor Trump's wish for no masks or social distancing.
  5. Business: Fed chair Powell says coronavirus is "great increaser" of income inequality.
  6. 1 sports thing: NCAA outlines plan to get athletes back to campus.