Male lake char release taurocholic acid as part of a mating pheromone

The evolutionary origins of sexual preferences for chemical signals remain poorly understood, due, in part, to scant information on the molecules involved. In the current study, we identified a male pheromone in lake char (Salvelinus namaycush) to evaluate the hypothesis that it exploits a nonsexual preference for juvenile odour. In anadromous char species, the odour of stream-resident juveniles guides migratory adults into spawning streams. Lake char are also attracted to juvenile odour but have lost the anadromous phenotype and spawn on nearshore reefs, where juvenile odour does not persist long enough to act as a cue for spawning site selection by adults.  Previous behavioural data raised the possibility that males release a pheromone that includes components of juvenile odour. Using metabolomics, we found that the most abundant molecule released by males was also released by juveniles but not females. Tandem mass spectrometry and nuclear magnetic resonance were used to identify the ..., , , # Male lake char release taurocholic acid as part of a mimetic pheromone

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Data include:

1. metabolomics results comparing chemical features of male, female, juvenile, and control water samples,
2. concentrations of taurocholic acid in male and female urine and conditioned water,
3. concentrations of taurocholic acid in male-conditioned water during and outside of the spawning season, and
4. behavioral responses of pre-spawning and spawning male and female lake char to taurocholic acid in two two-channel flumes.

## Description of the data and file structure

Metabolomics file:

* Water samples were collected by holding one male or female lake char, or 3 juveniles in 150 L of Lake Huron water for four hours.
* Peak1 through Peak5 are the relative magnitudes of the top five peaks found in male-conditioned water using high-resolution mass spectrometry.
* TCA is the concentration (ng/mL) of taurocholic acid in these water samples
* Juv.2 and Juv.3 are the weights and lengt...