ArticleProceedings of the National Academy of Sciences of the United States of America2019
Evolution of facial muscle anatomy in dogs.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 49 papers.
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49 citing papers in PubMed, 134 citations in OpenAlex.
- Descriptive, comparative, and functional anatomy of the facial musculature in cattle (Bos taurus).Anatomical record (Hoboken, N.J. : 2007) · 2026Article
- Beyond Domestication: Occurrence of Levator Anguli Oculi Medialis and Retractor Anguli Oculi Lateralis in Four Neotropical Canid Species.Anatomia, histologia, embryologia · 2026Article
- The Complexity of Communication in Mammals: From Social and Emotional Mechanisms to Human Influence and Multimodal Applications.Animals : an open access journal from MDPI · 2026Review
- An overview of the benefits of animal-assisted interventions in medical and therapeutic contexts for human health: cognitive mechanisms, sensory perception and welfare considerations.Frontiers in veterinary science · 2026Review
- Health implications of dog-worn equipment: a review of known and alleged physical risks.Frontiers in veterinary science · 2026Review
- Dogs display context-dependent behavioral responses to subtle owner-derived multimodal stimuli.Frontiers in veterinary science · 2026Article
- Specific Neural Mechanisms Underlying Humans' Processing of Information Related to Companion Animals: A Comparison with Domestic Animals and Objects.Animals : an open access journal from MDPI · 2025Article
- Anatomical and histological investigation of the effect of superoxide dismutase on eye muscles in Tuj sheep.Archives of Razi Institute · 2025Article
- Differences in dogs' and wolves' human-directed greeting behaviour: facial expressions, body language, and the problem of human biases.Animal cognition · 2025Article
- From Gaze to Interaction: Links Between Visual Attention, Facial Expression Identification, and Behavior of Children Diagnosed with ASD or Typically Developing Children with an Assistance Dog.Behavioral sciences (Basel, Switzerland) · 2025Article
- Evolutionary divergence of facial muscle physiology between domestic dogs and wolves.Anatomical record (Hoboken, N.J. : 2007) · 2025Article
- The cranial gland system of Nasonia spp.: a link between chemical ecology, evo-devo, and descriptive taxonomy (Hymenoptera: Chalcidoidea).Journal of insect science (Online) · 2025Article
- Quantifying Facial Gestures Using Deep Learning in a New World Monkey.American journal of primatology · 2025Article
- Suture obliteration patterns in wolves and a comparison to dogs.Scientific reports · 2025Article
- The neurobiological basis of emotions and their connection to facial expressions in non-human mammals: insights in nonverbal communication.Frontiers in veterinary science · 2025Review
- Comparative Analysis of Muscle Fibers in Selected Muscles of Working and Companion Dog Breeds.Animals : an open access journal from MDPI · 2024Article
- Neurobiology and Anatomy of Facial Expressions in Great Apes: Application of the AnimalFACS and Its Possible Association with the Animal's Affective State.Animals : an open access journal from MDPI · 2024Review
- Coyotes can do 'puppy dog eyes' too: comparing interspecific variation inRoyal Society open science · 2024Article
- Domestication constrains the ability of dogs to convey emotions via facial expressions in comparison to their wolf ancestors.Scientific reports · 2024Article
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5 authors at 4 institutions in 2 countries.
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No grant is acknowledged in the PubMed record.
Abstract
Domestication shaped wolves into dogs and transformed both their behavior and their anatomy. Here we show that, in only 33,000 y, domestication transformed the facial muscle anatomy of dogs specifically for facial communication with humans. Based on dissections of dog and wolf heads, we show that the levator anguli oculi medialis, a muscle responsible for raising the inner eyebrow intensely, is uniformly present in dogs but not in wolves. Behavioral data, collected from dogs and wolves, show that dogs produce the eyebrow movement significantly more often and with higher intensity than wolves do, with highest-intensity movements produced exclusively by dogs. Interestingly, this movement increases paedomorphism and resembles an expression that humans produce when sad, so its production in dogs may trigger a nurturing response in humans. We hypothesize that dogs with expressive eyebrows had a selection advantage and that "puppy dog eyes" are the result of selection based on humans' preferences.
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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.