Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Genome Size and the Evolution of New Genes03:21

Genome Size and the Evolution of New Genes

9.2K
While every living organism has a genome of some kind (be it RNA, or DNA), there is considerable variation in the sizes of these blueprints. One major factor that impacts genome size is whether the organism is prokaryotic or eukaryotic. In prokaryotes, the genome contains little to no non-coding sequence, such that genes are tightly clustered in groups or operons sequentially along the chromosome. Conversely, the genes in eukaryotes are punctuated by long stretches of non-coding sequence.
9.2K
Genome Size and the Evolution of New Genes03:21

Genome Size and the Evolution of New Genes

3.5K
3.5K
Convergent Evolution01:54

Convergent Evolution

33.0K
Evolution shapes the features of organisms over time, ensuring that they are suited for the environments in which they live. Sometimes, selection pressure leads to the rise of similar but unrelated adaptations in organisms with no recent common ancestors, a process known as convergent evolution.
33.0K
The Evidence for Evolution02:55

The Evidence for Evolution

48.3K
Genetic variations accumulating within populations over generations give rise to biological evolution. Evolutionary changes can result in the formation of novel varieties and entire new species. These changes are responsible for the diverse forms of life inhabiting the planet. The evidence for evolution suggests that all living organisms descended from common ancestors.
48.3K
Eukaryotic Evolution01:24

Eukaryotic Evolution

42.1K
The endosymbiont theory is the most widely accepted theory of eukaryotic evolution; however, its progression is still somewhat debated. According to the nucleus-first hypothesis, the ancestral prokaryote first evolved a membrane to enclose DNA and form the nucleus. Conversely, the mitochondria-first hypothesis suggests that the nucleus was formed after endosymbiosis of mitochondria.
Contrary to the endosymbiont theory, the eukaryote-first hypothesis proposes that the simpler prokaryotic and...
42.1K
Synteny and Evolution02:31

Synteny and Evolution

3.8K
John H. Renwick first coined the term “synteny” in 1971, which refers to the genes present on the same chromosomes, even if they are not genetically linked. The species with common ancestry tend to show conserved syntenic regions. Therefore, the concept of synteny is nowadays used to describe the evolutionary relationship between species.
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral...
3.8K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Sensorimotor Complexity and Cognition as Predictors of Primate Brain Size.

American journal of biological anthropology·2026
Same author

Making friends in an asymmetric game: the establishment of male-female grooming exchanges in vervet monkeys.

Proceedings. Biological sciences·2026
Same author

Parental investment and body temperature explain encephalization in vertebrates.

Proceedings of the National Academy of Sciences of the United States of America·2025
Same author

Slowly but Surely: Larger Brains Improve Immature Survival in Primates.

American journal of primatology·2025
Same author

Cooperative Breeding as a Likely Early Catalyst of Human Evolution.

Evolutionary anthropology·2025
Same author

Publisher Correction: Observational social learning of "know-how" and "know-what" in wild orangutans: evidence from nest-building skill acquisition.

Communications biology·2025

Related Experiment Video

Updated: Feb 7, 2026

An Experimental Study on Colorado Potato Beetle Hibernation Under Natural Conditions
07:44

An Experimental Study on Colorado Potato Beetle Hibernation Under Natural Conditions

Published on: November 17, 2023

13.4K

Hibernation constrains brain size evolution in mammals.

Sandra A Heldstab1, Karin Isler1, Carel P van Schaik1

  • 1Department of Anthropology, University of Zurich, Zurich, Switzerland.

Journal of Evolutionary Biology
|July 22, 2018
PubMed
Summary

Hibernating mammals have smaller relative brain sizes than non-hibernators. This supports the expensive brain hypothesis, suggesting energy constraints limit brain evolution, especially during seasonal food scarcity.

Keywords:
brain size evolutionenergy savingsheterothermyhibernationover-winteringseasonality

More Related Videos

A Noninvasive Hair Sampling Technique to Obtain High Quality DNA from Elusive Small Mammals
07:40

A Noninvasive Hair Sampling Technique to Obtain High Quality DNA from Elusive Small Mammals

Published on: March 13, 2011

21.4K
Mapping Cortical Dynamics Using Simultaneous MEG/EEG and Anatomically-constrained Minimum-norm Estimates: an Auditory Attention Example
08:45

Mapping Cortical Dynamics Using Simultaneous MEG/EEG and Anatomically-constrained Minimum-norm Estimates: an Auditory Attention Example

Published on: October 24, 2012

15.2K

Related Experiment Videos

Last Updated: Feb 7, 2026

An Experimental Study on Colorado Potato Beetle Hibernation Under Natural Conditions
07:44

An Experimental Study on Colorado Potato Beetle Hibernation Under Natural Conditions

Published on: November 17, 2023

13.4K
A Noninvasive Hair Sampling Technique to Obtain High Quality DNA from Elusive Small Mammals
07:40

A Noninvasive Hair Sampling Technique to Obtain High Quality DNA from Elusive Small Mammals

Published on: March 13, 2011

21.4K
Mapping Cortical Dynamics Using Simultaneous MEG/EEG and Anatomically-constrained Minimum-norm Estimates: an Auditory Attention Example
08:45

Mapping Cortical Dynamics Using Simultaneous MEG/EEG and Anatomically-constrained Minimum-norm Estimates: an Auditory Attention Example

Published on: October 24, 2012

15.2K

Area of Science:

  • Evolutionary biology
  • Comparative neuroanatomy
  • Metabolic research

Background:

  • The expensive brain hypothesis posits that high energy demands constrain brain size.
  • Periodic energy deficits may drive selection for reduced brain size relative to body mass.

Purpose of the Study:

  • To test if hibernation, an extreme energy-saving strategy, correlates with reduced relative brain size in mammals.
  • To investigate the role of environmental seasonality as an evolutionary constraint on brain size.

Main Methods:

  • A comparative phylogenetic analysis was performed on brain size data from 1104 mammalian species.
  • Statistical methods controlled for potential confounding variables affecting brain size.

Main Results:

  • The presence of hibernation in a mammalian species was significantly correlated with decreased relative brain size.
  • This finding held true after accounting for other evolutionary and ecological factors.

Conclusions:

  • Hibernation is associated with smaller relative brain sizes in mammals, supporting the expensive brain hypothesis.
  • Environmental seasonality, necessitating extreme energy conservation like hibernation, acts as an evolutionary constraint on brain size.