Old widows lie about their age – sexual conflict and mate-choice manipulation in false black widow spiders

Monday, November 14, 2022

11:30 AM – 11:42 AM PT

Location: Vancouver Convention Centre, Meeting Room 205

Presenting Author(s)

Andreas Fischer

PhD candidate
Simon Fraser University
Burnaby, British Columbia, Canada

Co-Author(s)

CR

Camilla Roman-Torres

Simon Fraser University
Burnaby, British Columbia, Canada
BC

Beatrice Chee

Simon Fraser University
Burnaby, British Columbia, Canada
GG

Gerhard Gries

Professor
Simon Fraser University
Burnaby, British Columbia, Canada

Across spider taxa, older females are generally more ‘appealing’ to
males than younger females, but the underlying mechanisms are not known.
Here, we investigated how aging of female false black widow spiders,
Steatoda grossa (Theridiidae), affects their sexual signaling and
reproductive output. Age-dependently, the reproductive output of females
significantly declined. Older females also produced less dense webs and
deposited less courtship-inducing contact pheromone on their webs than
younger females, as determined by high performance liquid chromatography
– mass spectrometry. However, in Y-tube olfactometers, the webs of old
females remained as attractive to mate-seeking males as the webs of
young females. It follows that old females manipulate the mate choice of
males that would attain greater reproductive fitness by mating with
younger females.