ArticleDie Naturwissenschaften2016
Side-specific effect of yolk testosterone elevation on second-to-fourth digit ratio in a wild passerine.
Article in Die Naturwissenschaften, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers, 2 of them syntheses 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
6 citing papers in PubMed, 2 syntheses or guidelines pooled it, 18 citations in OpenAlex.
- Do Egg Hormones Have Fitness Consequences in Wild Birds? A Systematic Review and Meta-Analysis.Ecology letters · 2025Pooled it
- In support of 2D:4D: More data exploring its conflicting results on handedness, sexual orientation and sex differences.PloS one · 2023Pooled it
- Digit ratio in the common toad Bufo bufo: the effects of reduced fingers and of age dependency.Zoological letters · 2021Article
- Sand lizards Lacerta agilis with higher digit ratios are more likely to autotomy.Journal of anatomy · 2020Article
- Digit ratio predicts the number of lifetime recruits in female collared flycatchers.Biology letters · 2019Article
- Phenotypic integration mediated by hormones: associations among digit ratios, body size and testosterone during tadpole development.BMC evolutionary biology · 2017Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Second-to-fourth digit ratio is a widely investigated sexually dimorphic morphological trait in human studies and could reliably indicate the prenatal steroid environment. Conducting manipulative experiments to test this hypothesis comes up against ethical limits in humans. However, oviparous tetrapods may be excellent models to experimentally investigate the effects of prenatal steroids on offspring second-to-fourth digit ratio. In this field study, we injected collared flycatcher (Ficedula albicollis) eggs with physiological doses of testosterone. Fledglings from eggs with elevated yolk testosterone, regardless of their sex, had longer second digits on their left feet than controls, while the fourth digit did not differ between groups. Therefore, second-to-fourth digit ratio was higher in the testosterone-injected group, but only on the left foot. This is the first study which shows experimentally that early testosterone exposure can affect second-to-fourth digit ratio in a wild population of a passerine bird.
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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.