Transformational Mimicry in a Myrmecomorphic Spider.

Area of Science:

• Ecology
• Evolutionary Biology
• Behavioral Ecology

Background:

• Batesian mimicry involves a palatable species mimicking an unpalatable one.
• Some species change their mimetic models during development, a phenomenon known as transformational mimicry.
• It is unclear if successive mimetic phenotypes offer consistent protection against predators.

Purpose of the Study:

• To test the hypothesis of transformational Batesian mimicry in the ant-mimicking jumping spider Leptochestes berolinensis.
• To quantify the mimetic accuracy of different developmental stages of L. berolinensis to various ant models.
• To assess predator responses to different mimicry stages.

Main Methods:

• A multitrait approach was used to quantify mimicry, including movement, body profile, size, and coloration.
• Mimetic accuracy was compared across juvenile and adult stages of L. berolinensis.
• Predator deception experiments were conducted using mantises and Pisaura spiders, with prior experience of ant models.

Main Results:

• Adult L. berolinensis were found to be more accurate mimics than juveniles.
• Adult mimics resembled smaller ants (Camponotus, Lasius), while juveniles mimicked Lasius and Colobopsis ants.
• Predators (mantises, Pisaura spiders) did not capture ants or mimics, but consistently captured the non-mimicking spider, indicating effective mimicry across stages.

Conclusions:

• Leptochestes berolinensis demonstrates transformational Batesian mimicry, shifting models during ontogeny.
• All developmental stages of L. berolinensis are accurate mimics, providing protection from key predators.
• The study supports the effectiveness of Batesian mimicry throughout postembryonic development.