Related Experiment Video
Updated: May 16, 2026

Assessing Intertidal Populations of the Invasive European Green Crab
Published on: September 16, 2020
Population divergence of the sentinel crab Macrophthalmus banzai is consistent with regional breeding season
Misuzu Aoki1, Yukari Nakagawa, Mayuko Kawamoto
1KYOUSEl Science Center for Life and Nature, Nara Women's University, Kitauoya-higashimachi, Nara 630-8506, Japan.
Abstract:
We compared the breeding season and genetic population structure of six sentinel crab (Macrophthalmus banzai) populations in southwestern Japan. Ovigerous females from Northern group populations (Wakayama, Kochi, and Tanega-shima) were observed from March to September, whereas ovigerous females from Southern group populations (Amami-oshima, Okinawa-jima, and Iriomote-jima) were observed from October to May. Genetic analysis using two markers corresponding to mitochondrial DNA encoding cytochrome oxidase subunit I (COI) and the large subunit of ribosomal RNA (16Sr-RNA) revealed a marked genetic difference between the Northern and Southern groups. A genetic boundary exists between the Tanega-shima and Amami-oshima populations, which is consistent with the interpopulation difference in the breeding season.
Related Concept Videos
Speciation Rates
Migration
Types of Selection
Convergent Evolution
Hybrid Zones
Testing a Claim about Mean: Known Population SD
Estimating a population mean requires the samples to be distributed normally. The data should be collected from the randomly selected samples having no sampling bias. The sample size needed to be higher than 30, and most importantly, the population standard deviation should be already known.
In most realistic situations, the population standard deviation is often unknown, but in rare circumstances, when it...

