Study
The function of bilateral odor arrival time differences in olfactory orientation of sharks
Gardiner, Jayne M.; Atema, Jelle
Current Biology, 2010
Sharks were fitted with apparatus that delivered an odour pulse to each nostril separately, with the delay between the two sides controlled. The direction the animal turned was recorded against which nostril received the odour first and by how much.
- Studied in
- Mustelus canis
- Sample size
- smooth dogfish fitted with headgear delivering odour to each nostril independently
Sharks turned towards the side that received the odour first, for delays of roughly a tenth of a second down to a fraction of that, and did not respond to differences in concentration between the two sides.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Sharks steer in an odour plume by comparing the arrival time at the two nostrils, not by comparing concentration.
How NatureHQ reads it
The result that replaces the standard picture of smell-tracking. Everybody assumes an animal compares how strong the smell is on each side and turns towards the stronger — and a real plume is a turbulent mess of filaments in which concentration at any instant carries almost no directional information. Timing does. This is the same solution ears use for locating sound, applied to chemistry, and it explains how a shark can hold a heading in water where the concentration gradient is nonsense.
- One species, restrained and instrumented, which constrains natural swimming.
- Establishes the cue used for steering, not the distance over which a plume can be followed.
- Concentration comparison may still contribute at very different timescales.
Delivering a smell to one shark nostril a fraction of a second before the other
A shark following a scent has to decide which way to turn. Is it comparing how strong the smell is on each side?
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Smell, and how far it really works
A shark following a smell turns towards whichever nostril detected it first, not towards the side where it is strongest — because in a real plume, strength tells you almost nothing.
Smell, and how far it really works
A male silk moth’s antenna responds to a single molecule of pheromone. That is the physical limit of sensitivity, and it is not what lets him cross a field to find a female — the flight strategy does that.
Published by: Cell PressPublished in a Cell Press journal.
doi.org/10.1016/j.cub.2010.04.053
Checked against Crossref on 2026-09-28, and they agree on the title, the authors and the year.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-09-02.