ArticleScientific reports2021
Sexual dimorphism in size and shape of the head in the sea snake Emydocephalus annulatus (Hydrophiinae, Elapidae).
Article in Scientific reports, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 8 papers, 1 of them a synthesis that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
8 citing papers in PubMed, 1 synthesis or guideline pooled it, 10 citations in OpenAlex.
- Pooled it
- Divergent Paths, Convergent Heads: Morphological Adaptation of Head Shape to Habitat Use and Diet in Snakes.Journal of morphology · 2025Article
- Adaptive divergence in diets between the sexes in a tropical snake (Stegonotus australis, Colubridae).Oecologia · 2025Article
- Behavior and Activity Patterns of the Critically Endangered Mangshan Pit Viper (Animals : an open access journal from MDPI · 2024Article
- Sexual dimorphism in aipysurine sea snakes (Elapidae, Hydrophiinae).Royal Society open science · 2023Article
- Can diet niche partitioning enhance sexual dimorphism?Ecology and evolution · 2022Article
- Sexual dimorphism and reproductive biology of the Asian bockadam snake (Cerberus schneiderii) in West Java.Scientific reports · 2022Article
- Sexual Dimorphism in the Chinese Endemic SpeciesAnimals : an open access journal from MDPI · 2022Article
Corrections and comments
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Authors and funding
2 authors at 2 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
In snakes, divergence in head size between the sexes has been interpreted as an adaptation to intersexual niche divergence. By overcoming gape-limitation, a larger head enables snakes of one sex to ingest larger prey items. Under this hypothesis, we do not expect a species that consumes only tiny prey items to exhibit sex differences in relative head size, or to show empirical links between relative head size and fitness-relevant traits such as growth and fecundity. Our field studies on the sea snake Emydocephalus annulatus falsify these predictions. Although these snakes feed exclusively on fish eggs, the heads of female snakes are longer and wider than those of males at the same body length. Individuals with wider heads grew more rapidly, reproduced more often, and produced larger litters. Thus, head shape can affect fitness and can diverge between the sexes even without gape-limitation. Head size and shape may facilitate other aspects of feeding (such as the ability to scrape eggs off coral) and locomotion (hydrodynamics); and a smaller head may advantage the sex that is more mobile, and that obtains its prey in narrow crevices rather than in more exposed situations (i.e., males).
Indexed as
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What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.