Nav: Home

How big brains evolved could be revealed by new mathematical model

March 09, 2017

A new mathematical model could help clarify what drove the evolution of large brains in humans and other animals, according to a study published in PLOS Computational Biology.

Animals with high cognitive ability also have relatively large brains, but the factors that drive evolution of big brains remain unclear. Scientists have hypothesized that ecological, social, and cultural factors could each play a role. Most of these hypotheses have not been formalized mathematically, but doing so would allow scientists to refine their tests.

To address the issue, Mauricio González-Forero of University of Lausanne, Switzerland, and colleagues developed a mathematical model that predicts how large the human brain should be at different stages of an individual's life, depending on different possible evolutionary scenarios.

The model relies on the assumption that the brain expends some energy on cognitive skills that allow an individual to extract energy from the environment (food), which in turn helps the brain grow. Given natural selection, it predicts how much energy is used to support brain growth at different ages under different biological settings.

The researchers used the model to test a simple scenario in which social interactions and cultural factors are excluded, revealing the influence of ecological factors alone. In the scenario, a human must hunt or gather food alone, but may receive some help from its mother while it is still young.

Under those specifications, the hypothetical human brain grew as big as ancient humans' brains are thought to have grown, and the slow growth rate matched that of modern human brains. This runs counter to prevailing thought, which holds that social and cultural influences are required to achieve these sizes and growth rates.

"Our findings raise new questions about the effects and interactions of ecological, social, and cultural factors, and our framework offers a new tool to address them," González-Forero says. "More broadly, our framework allows for new experiments in silico to study brain evolution, life history, and brain senescence."

His team is now using the new model to investigate how social factors may influence evolution of large brain size. In the future, they hope to test cultural factors as well.
-end-
In your coverage please use this URL to provide access to the freely available article in PLOS Computational Biology: http://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1005380

Citation: González-Forero M, Faulwasser T, Lehmann L (2017) A model for brain life history evolution. PLoS Comput Biol 13(2): e1005380. doi:10.1371/journal.pcbi.1005380

Funding: This work was funded by Swiss NSF grant PP00P3-146340 to LL http://www.snf.ch/en/Pages/default.aspx. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing Interests: The authors have declared that no competing interests exist.

PLOS

Related Evolution Articles:

A window into evolution
The C4 cycle supercharges photosynthesis and evolved independently more than 62 times.
Is evolution predictable?
An international team of scientists working with Heliconius butterflies at the Smithsonian Tropical Research Institute (STRI) in Panama was faced with a mystery: how do pairs of unrelated butterflies from Peru to Costa Rica evolve nearly the same wing-color patterns over and over again?
Predicting evolution
A new method of 're-barcoding' DNA allows scientists to track rapid evolution in yeast.
Insect evolution: Insect evolution
Scientists at Ludwig-Maximilians-Universitaet (LMU) in Munich have shown that the incidence of midge and fly larvae in amber is far higher than previously thought.
Evolution of aesthetic dentistry
One of the main goals of dental treatment is to mimic teeth and design smiles in the most natural and aesthetic manner, based on the individual and specific needs of the patient.
An evolution in the understanding of evolution
In an open-source research paper, a UVA Engineering professor and her former Ph.D. student share a new, more accurate method for modeling evolutionary change.
Chemical evolution -- One-pot wonder
Before life, there was RNA: Scientists at Ludwig-Maximilians-Universitaet (LMU) in Munich show how the four different letters of this genetic alphabet could be created from simple precursor molecules on early Earth -- under the same environmental conditions.
Catching evolution in the act
Researchers have produced some of the first evidence that shows that artificial selection and natural selection act on the same genes, a hypothesis predicted by Charles Darwin in 1859.
Guppies teach us why evolution happens
New study on guppies shows that animals evolve in response the the environment they create in the absence of predators, rather than in response to the risk of being eaten.
Undercover evolution
Our individuality is encrypted in our DNA, but it is deeper than expected.
More Evolution News and Evolution Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

In & Out Of Love
We think of love as a mysterious, unknowable force. Something that happens to us. But what if we could control it? This hour, TED speakers on whether we can decide to fall in — and out of — love. Guests include writer Mandy Len Catron, biological anthropologist Helen Fisher, musician Dessa, One Love CEO Katie Hood, and psychologist Guy Winch.
Now Playing: Science for the People

#543 Give a Nerd a Gift
Yup, you guessed it... it's Science for the People's annual holiday episode that helps you figure out what sciency books and gifts to get that special nerd on your list. Or maybe you're looking to build up your reading list for the holiday break and a geeky Christmas sweater to wear to an upcoming party. Returning are pop-science power-readers John Dupuis and Joanne Manaster to dish on the best science books they read this past year. And Rachelle Saunders and Bethany Brookshire squee in delight over some truly delightful science-themed non-book objects for those whose bookshelves are already full. Since...
Now Playing: Radiolab

An Announcement from Radiolab