Review

Poor human olfaction is a 19th-century myth

See allHide authors and affiliations

Science  12 May 2017:
Vol. 356, Issue 6338, eaam7263
DOI: 10.1126/science.aam7263

eLetters is an online forum for ongoing peer review. Submission of eLetters are open to all. eLetters are not edited, proofread, or indexed.  Please read our Terms of Service before submitting your own eLetter.

Compose eLetter

Plain text

  • Plain text
    No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.
Author Information
First or given name, e.g. 'Peter'.
Your last, or family, name, e.g. 'MacMoody'.
Your email address, e.g. higgs-boson@gmail.com
Your role and/or occupation, e.g. 'Orthopedic Surgeon'.
Your organization or institution (if applicable), e.g. 'Royal Free Hospital'.
Statement of Competing Interests
CAPTCHA

This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.

Image CAPTCHA
Enter the characters shown in the image.

Vertical Tabs

  • RE: The forgotten organ
    • Biagio D'Aniello, Professor, Department of Biology, University of Naples “Federico II”, MSA Campus, Naples, Italy
    • Other Contributors:
      • Anna Scandurra, Post Doc, Department of Biology, University of Naples “Federico II”, MSA Campus, Naples, Italy
      • Gün Refik Semin, Professor, William James Center for Research, ISPA-IU, Lisbon, Portugal
      • Claudia Pinelli, Researcher, Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania, Caserta, Ita

    In this excellent article, John P. McGann highlights the “olfactory abilities” of humans compared to other mammals arguing that “poor human olfaction is a 19th-century myth”. At the same time, he argues: "Humans lack the “accessory” olfactory system (AOS), a set of parallel structures including the vomeronasal organ and accessory olfactory bulb found in many other animals”. While this observation is probably true in the case of the accessory olfactory bulbs (AOBs), it is incorrect for the vomeronasal organ (VNO). Paradoxically, this organ was first observed in humans and only subsequently in other mammals. The discovery of the VNO is historically ascribed to the 17th-18th-century Dutch anatomist Frederik Ruysch (1). It is said that during the intervention of a soldier, in an attempt to curb a deep wound on his face, he observed the presence of a small organ adjacent the nasal septum. While this remains anecdotal, Ruysch provides a clear description of an organ near the nasal septum of a human infant (1) without giving it a name, or an accurate description. Consequently, some authors (2) attribute the honor of discovering the human VNO to Kölliker (3), who was the first among 18th–19th-century investigators to provide evidence of the human VNO as a histologically identifiable structure, both in the fetus and the adult.
    The VNO was deeply studied by Jacobson (4) in a variety of mammals, although he explicitly denied its presence in humans (perhaps Jacobson was not...

    Show More
    Competing Interests: None declared.
  • RE: Humans are macrosmatic in everyday life: evidence from anthropology and cultural history
    • Benoist Schaal, Behavioral biologist, Centre des Sciences du Goût, CNRS-Université de Bourgogne, Dijon, France
    • Other Contributors:
      • Joël Candau, anthropologist, Laboratoire d'Anthropologie et de Psychologie Cognitives et Sociales, Université Côte d'Azur, Nice, France

    In his excellent review, based on neuroanatomical and biomedical data, John P. McGann convincingly proposes that the human sense of smell is not disadvantaged compared to that of other mammals classified as macrosmatic. However, the human perceptual and behavioral evidence he uses in support of his analysis stems from Western laboratory studies rather than from real-life situations, world-wide and across times. As olfactory perception, knowledge and valuation are also cultural facts (Le Guérer A., Scent, Turtle Bay Books 1992; Classen C., et al., Aroma, Routledge, 1995), further evidence from anthropology and cultural history may compellingly generalize his thesis.
    Regarding their most basic ways of material subsistence (through gathering, hunting, gardening or farming), humans rely on olfaction to detect, select, and concoct vegetal, fungal or animal items used as food, medicinal, esthetic or domestic commodities (e.g., Brett J., J. Appl. Bot. 72, 70-74, 1998; Pierroni A. & Torry B., J. Ethnobiol Ethnomed., 3:21; 2007; Turner J., Ancient pathways, Ancestral knowledge, McGill-Queen's Univ. Press, 2014). Odor and flavor perception are indeed of universal concern for the human expertise applied to optimize the balance between the nutritional, toxic and sensory/hedonic properties of foods and beverages (Wrangham R., Catching fire, Basic Books, 2009; Shepherd G., Neurogastronomy, Columbia Univ. Press, 2012). In independent foci all over the world ways to process...

    Show More
    Competing Interests: None declared.
  • RE: Poor human olfaction is a 19th-century myth
    • Fatima Cvrčková, Biologist and educator, Faculty of Sciences, Charles University, Prague, Czechia

    Reflecting the overall fashion of the time, in the 1880s to 1930s it was rather hard to find a non-smoker senior intellectual. Indeed, Paul Broca himself was a very heavy cigar smoker (see Schiller, Paul Broca: Founder of French Anthropology, Explorer of the Brain, University of California Press 1979, p. 287), while Sir William Turner allegedly enjoyed a regular after-dinner cigar (see Turner: Sir William Turner: A Chapter in medical history. Blackwood, Edinburgh 1919, p. 483). Sigmund Freud´s passion for tobacco (and the resulting mouth cancer) is generally known. Since tobacco smoking is well known to impair odor perception (e.g., Vennemann et al, J Neurol. 2008, 255(8):1121-6. doi: 10.1007/s00415-008-0807-9), the myth of human congenital anosmia (or microsmia) may have reflected a very personal experience of its original authors and propagators, besides of various theoretical rationales mentioned in this excellent review.

    Competing Interests: None declared.
  • RE: Plenty opportunities for research

    Thank you, Dr. John P. McGann, for this insightful review. I enjoyed reading about the context Broca’s bias in 19th-century France. This review highlighted for me yet again, the importance of performing a literature review (sometimes going back a century!) and a need for open peer-review.

    In my opinion, a big part of the challenge in olfaction science is the apparent paucity of solid data for detection thresholds for both humans and animals. Published work on detection thresholds can be confounded by the lack of proper engineering support, e.g., lack of proper apparatuses to generate standard gas concentrations of odorants and proper means to deliver them to humans and animals. Relatively few published sources appear to control for that. Methodological differences and experimental approached can confound measured detection thresholds. See Table 1 in Rice and Koziel (2015): https://doi.org/10.1016/j.dib.2015.09.053.

    There is still plenty of opportunities to engage in applied research and establish (or improve) detection thresholds for humans and animals. Some comparative work using the same methodology/apparatuses would be welcome.

    Another challenge is the apparent assumption that gas concentrations are correlated with odor perception, that can be paraphrased by:

    ‘high gas concentration = intense odor’.

    More often than not, it is not the case. Using simultaneous chemical...

    Show More
    Competing Interests: None declared.