Navigation Links
Big brains are pricey, guppy study shows

Bigger brains can make animals, well, brainier, but that boost in brain size and ability comes at a price. That's according to new evidence reported on January 3rd in Current Biology, a Cell Press publication, in which researchers artificially selected guppies for large and small brain sizes.

The findings lend support to the notion that bigger brains and increased cognitive ability do go together, a topic that has been a matter of considerable debate in recent years, said Niclas Kolm of Uppsala University in Sweden. They also represent some of the first convincing evidence that large brains are expensive, evolutionarily speaking.

"We provide the first experimental evidence that evolving a larger brain really is costly in terms of both gut investment and, more importantly, reproductive output," Kolm said.

Together, the findings strongly support the idea that relative brain sizes among species are shaped through a balance between selection for increased cognitive ability and the costs of a big brain.

The results in guppies have important implications for us humans. After all, one of the most distinctive features of the human brain is its large size relative to the rest of the body.

"The human brain only makes up 2 percent of our total body mass but stands for 20 percent of our total energy demand," Kolm said. "It is a remarkably costly organ energetically."

But support for the so-called "expensive-tissue hypothesis"that there is a trade-off between the brain and the energy demands of other organs and reproductioncame only from comparative studies among species and were correlative in nature.

In the new study, Kolm's team took a different, within-species approach. They selected live-bearing guppies for large and small brains relative to the size of their bodies. Under that strong selection pressure, they found that brain size could evolve "remarkably quickly."

After selection, large-brained guppies outscored their smaller-brained peers in a test of numerical learning. With more energy devoted to brain-building, brainy fishmales especiallydid have smaller guts. They also left fewer offspring to the next generation.

Those effects were observed despite the fact that the fish were supplied with an abundance of food. The researchers say they are curious to see what will happen in future experiments with fish in a more competitive, semi-natural environment including limited resources and predators.

The findings lead Kolm and his colleagues to suggest that the relatively small family sizes of humans and other primates, not to mention dolphins and whales, might have helped to make our big brains possible.


Contact: Mary Beth O'Leary
Cell Press

Related biology news :

1. Musical duets lock brains as well as rhythms
2. Primates brains make visual maps using triangular grids
3. Preemies brains reap long-term benefits from Kangaroo Mother Care
4. Mice with big brains provide insight into brain regeneration and developmental disorders
5. University of Alberta led research may have discovered how memories are encoded in our brains
6. Hebrew University study finds key mechanism in calcium regulation
7. New study documents the natural relationship between CO2 concentrations and sea level
8. Stowers study hints that stem cells prepare for maturity much earlier than anticipated
9. Birdsong study pecks theory that music is uniquely human
10. Study turns parasite invasion theory on its head
11. Gout study offers genetic insight into disease of kings
Post Your Comments:
(Date:11/12/2015)... golden retriever that stayed healthy despite having the gene ... new lead for treating this muscle-wasting disorder, report scientists ... and Harvard and the University of São Paolo in ... pinpoints a protective gene that boosts muscle regeneration, ... Children,s lab of Lou Kunkel , PhD, is ...
(Date:11/10/2015)... Nov. 10, 2015 About ... that helps to identify and verify the identity ... considered as the secure and accurate method of ... a particular individual because each individual,s signature is ... especially when dynamic signature of an individual is ...
(Date:10/29/2015)... Oct. 29, 2015   MedNet Solutions , an ... spectrum of clinical research, is pleased to announce that ... Association (MHTA) as one of only three finalists for ... – Small and Growing" category. The Tekne Awards honor ... shown superior technology innovation and leadership. ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... LUMPUR, Malaysia , Nov. 24, 2015 /PRNewswire/ ... global contract research organisation (CRO) market. The trend ... result in lower margins but higher volume share ... increased capacity and scale, however, margins in the ... Research Organisation (CRO) Market ( ), ...
(Date:11/24/2015)... 2015 Halozyme Therapeutics, Inc. (NASDAQ: HALO ) will ... New York on Wednesday, December 2 at 9:30 a.m. ... and CEO, will provide a corporate overview. th ... at 1:00 p.m. ET/10:00 a.m. PT . Jim Mazzola ... a corporate overview. --> th Annual Oppenheimer Healthcare ...
(Date:11/24/2015)... ... November 24, 2015 , ... ... the year and one of the premier annual events for pharmaceutical manufacturing: 2015 ... 8–11 November 2015, where ISPE hosted the largest number of attendees in more ...
(Date:11/24/2015)... 2015 --> ... "Oligonucleotide Synthesis Market by Product & Services (Primer, Probe, ... DNA, RNAi), End-User (Research, Pharmaceutical & Biotech, Diagnostic Labs) ... market is expected to reach USD 1,918.6 Million by ... CAGR of 10.1% during the forecast period. ...
Breaking Biology Technology: