ArticleBiology letters2020
The longer the better: evidence that narwhal tusks are sexually selected.
Article in Biology letters, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 10 papers.
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Who cites it
10 citing papers in PubMed, 36 citations in OpenAlex.
- The narwhal tusk assembles its macroscopic helix from building blocks with opposing twists.Nature communications · 2026Article
- Impact of Tusk Anomalies on the Long-Term Foraging Ecology of Narwhals.Ecology and evolution · 2025Article
- Strong bat predation and weak environmental constraints predict longer moth tails.Proceedings. Biological sciences · 2025Article
- Males armed with big weapons win fights at limited cost in ant-mimicking jumping spiders.Current zoology · 2024Article
- A new fossil dolphin with tusk-like teeth from New Zealand and an analysis of procumbent teeth in fossil cetaceans.Journal of the Royal Society of New Zealand · 2024Article
- A new dolphin with tusk-like teeth from the late Oligocene of New Zealand indicates evolution of novel feeding strategies.Proceedings. Biological sciences · 2023Article
- Unconventional animal models for traumatic brain injury and chronic traumatic encephalopathy.Journal of neuroscience research · 2021Review
- Population-specific sex and size variation in long-term foraging ecology of belugas and narwhals.Royal Society open science · 2021Article
- Armed stem to stinger: a review of the ecological roles of scorpion weapons.The journal of venomous animals and toxins including tropical diseases · 2021Review
- The longer the better: evidence that narwhal tusks are sexually selected.Biology letters · 2020Article
Corrections and comments
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Authors and funding
4 authors at 3 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Once thought to be the magical horn of a unicorn, narwhal tusks are one of the most charismatic structures in biology. Despite years of speculation, little is known about the tusk's function, because narwhals spend most of their lives hidden underneath the Arctic ice. Some hypotheses propose that the tusk has sexual functions as a weapon or as a signal. By contrast, other hypotheses propose that the tusk functions as an environmental sensor. Since assessing the tusks function in nature is difficult, we can use the morphological relationships of tusk size with body size to understand this mysterious trait. To do so, we collected morphology data on 245 adult male narwhals over the course of 35 years. Based on the disproportional growth and large variation in tusk length we found, we provide the best evidence to date that narwhal tusks are indeed sexually selected. By combining our results on tusk scaling with known material properties of the tusk, we suggest that the narwhal tusk is a sexually selected signal that is used during male-male contests.
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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.