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

Wald-Wolfowitz Runs Test II01:17

Wald-Wolfowitz Runs Test II

318
The Wald-Wolfowitz runs test, commonly referred to as the runs test, is a nonparametric test used to assess the randomness of ordered data. The test evaluates the number of runs, which are consecutive sequences of similar elements within the data. If the number of runs is significantly higher or lower than expected, the data is considered non-random, indicating a detectable pattern or structure.
For binary data, runs are identified using symbols such as + and −, or equivalently, 1s and...
318
Testing a Claim about Mean: Unknown Population SD01:21

Testing a Claim about Mean: Unknown Population SD

3.6K
A complete procedure of testing a hypothesis about a population mean when the population standard deviation is unknown is explained here.
Estimating a population mean requires the samples to be approximately normally distributed. The data should be collected from the randomly selected samples having no sampling bias. There is no specific requirement for sample size. But if the sample size is less than 30, and we don't know the population standard deviation, a different approach is used;...
3.6K
Evolutionary Relationships through Genome Comparisons02:54

Evolutionary Relationships through Genome Comparisons

6.2K
Genome comparison is one of the excellent ways to interpret the evolutionary relationships between organisms. The basic principle of genome comparison is that if two species share a common feature, it is likely encoded by the DNA sequence conserved between both species. The advent of genome sequencing technologies in the late 20th century enabled scientists to understand the concept of conservation of domains between species and helped them to deduce evolutionary relationships across diverse...
6.2K
Convergent Evolution01:54

Convergent Evolution

29.0K
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.
29.0K
Testing a Claim about Population Proportion01:24

Testing a Claim about Population Proportion

3.4K
A complete procedure for testing a claim about a population proportion is provided here.
There are two methods of testing a claim about a population proportion: (1) Using the sample proportion from the data where a binomial distribution is approximated to the normal distribution and (2) Using the binomial probabilities calculated from the data.
The first method uses normal distribution as an approximation to the binomial distribution. The requirements are as follows: sample size is large...
3.4K
Speciation Rates01:07

Speciation Rates

21.4K
Overview
21.4K

You might also read

Related Articles

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

Sort by
Same author

The functional significance of striping in rodents.

Evolution; international journal of organic evolution·2026
Same author

Tourism puts Zanzibari reserve at a crossroads.

Science (New York, N.Y.)·2025
Same author

The Adaptive Significance of Tail-Flagging: A Test in European Rabbits (<i>Oryctolagus cuniculus</i>).

Ecology and evolution·2025
Same author

Spatio-temporal metapopulation trends: The coconut crabs of Zanzibar.

Ecology and evolution·2024
Same author

The Evolution of Rodent Tail Morphology.

The American naturalist·2024
Same author

Outstanding issues in the study of antipredator defenses.

Ecology and evolution·2023

Related Experiment Video

Updated: Sep 13, 2025

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

21.0K

Gloger's Rule or Historical Conjecture? Tests in Mammals.

Natasha Howell1, Tim Caro1,2

  • 1School of Biological Sciences University of Bristol Bristol UK.

Ecology and Evolution
|July 28, 2025
PubMed
Summary

Mammals are darker in humid tropical regions, supporting Gloger's rule. However, contrary to 19th-century ideas, mammals in the tropics are not more brightly colored or patterned.

Keywords:
19th‐century naturalistsConstantin GlogerGloger's rulebackground matchingcrypsisecogeographical rulesmammal coloration

More Related Videos

Standardizing a Non-Lethal Method for Characterizing the Reproductive Status and Larval Development of Freshwater Mussels Bivalvia: Unionida
07:22

Standardizing a Non-Lethal Method for Characterizing the Reproductive Status and Larval Development of Freshwater Mussels Bivalvia: Unionida

Published on: October 4, 2019

7.9K
Tracing Gene Expression Through Detection of &#946;-galactosidase Activity in Whole Mouse Embryos
08:42

Tracing Gene Expression Through Detection of β-galactosidase Activity in Whole Mouse Embryos

Published on: June 26, 2018

26.7K

Related Experiment Videos

Last Updated: Sep 13, 2025

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

21.0K
Standardizing a Non-Lethal Method for Characterizing the Reproductive Status and Larval Development of Freshwater Mussels Bivalvia: Unionida
07:22

Standardizing a Non-Lethal Method for Characterizing the Reproductive Status and Larval Development of Freshwater Mussels Bivalvia: Unionida

Published on: October 4, 2019

7.9K
Tracing Gene Expression Through Detection of &#946;-galactosidase Activity in Whole Mouse Embryos
08:42

Tracing Gene Expression Through Detection of β-galactosidase Activity in Whole Mouse Embryos

Published on: June 26, 2018

26.7K

Area of Science:

  • Zoology
  • Ecology
  • Evolutionary Biology

Background:

  • Gloger's rule predicts darker coloration in homeotherms at lower latitudes.
  • 19th-century naturalists proposed increased conspicuous coloration in tropical species.
  • Mammalian coloration patterns require further investigation across diverse environments.

Purpose of the Study:

  • To test Gloger's rule and 19th-century conjectures on mammalian coloration.
  • To investigate the influence of latitude, humidity, and temperature on mammal coloration.
  • To analyze coloration patterns across different body regions (head, torso, legs, tail).

Main Methods:

  • Phylogenetic comparative methods applied to 2726 mammal species.
  • Coloration data from photographs compared with a specialized mammal color chart.
  • Ecological data sourced from open-access databases.
  • Bayesian phylogenetic comparative generalized linear mixed models used for analysis.

Main Results:

  • Strong evidence for darker mammal coloration in tropics, high precipitation, and evapotranspiration zones.
  • Limited support for darker coloration in warmer areas or redder coloration in arid regions.
  • No support for increased conspicuous coloration, contrast, or patterning in tropical mammals.
  • Findings consistent across class and order levels, confirming Gloger's rule facet.

Conclusions:

  • Eumelanic coloration is more prevalent in humid climates across mammals, supporting Gloger's rule.
  • 19th-century observations of bright tropical coloration do not apply to mammals.
  • Darker mammalian coloration is macroecologically linked to humidity.