Ep. 38 - Ants in Our Plants

Have you ever heard of myrmecochory? It may not pop up much in casual conversation, but this strange word is your doorway to a tiny, fascinating world of ant-plant interactions. Myrmecochory is seed dispersal by ants (don’t worry, we cover how to pronounce it in the episode), and while it may seem simple on the surface, it’s a beautifully complex spectrum of behaviors and benefits, including some questionable ones.

Myrmecochory has long been considered a classic example of mutualism, in which two species benefit from a shared interaction, but recent research has called this idea into question. Are the ants really benefiting? Is it possible that plants are parasitizing the ants? Are the ants inadvertently ‘cleaning’ the seeds, inoculating them against harmful soil microbes? There is so much more to myrmecochory than Bill and Steve ever imagined! Join the guys as they hit the trail, exploring the seldom-seen world of ants and plants.

This episode was recorded at Nature View Park in Amherst, NY on April 24, 2019. Nature View is owned by the Western New York Land Conservancy.

Get the episode transcript.

Episode Notes

Steve wondered what the technical term is for someone who studies ants. We should have known - they’re called myrmecologists!

Cricket vs. chorus frog - which did we hear? The frog heard calling during the episode is the western chorus frog (Pseudacris triseriata).

At the 8:15 mark, Steve wondered if there was a word for seed dispersal syndrome, similar to terms related to pollination syndrome. There are a range of terms for each. Wikipedia gives a decent basic overview on pollination syndrome and seed dispersal syndrome.

Steve wondered if leaf-cutter ants have metapleural glands (those glands that produce antimicrobial compounds). Bill said he didn’t think so, but he was wrong! Currently, researchers aren’t sure if ants can control the excretions from their metapleural glands, but there is some evidence that they may.

Do ephemerals need ants? During the episode, Steve wondered if this relationship was required by spring ephemerals. That is, do these spring wildflowers need ants in order to maintain their populations in a habitat? We’re still looking into a definitive answer on this one.

Photo (and title) credit: We have to give a shout out to the great nature blog Roads End Naturalist. They had a great post on myrmecochory from which we used this episode’s photo and title.

Thanks also to listener Joe Stormer for transcribing this and other episodes.

Links

Check out the history of Nature View Park and consider supporting the Western New York Land Conservancy or your local land conservancy/land trust. These groups are doing some of the most vital local biodiversity conservation work in habitats across the continent!

The In Defense of Plants episode that inspired this episode can be found here.

Also check out their great blog post about myrmecochory.

And if you want to find the latest research into myrmecochory, check out the Myrmecoolgical News blog!

Sponsorship of this episode provided by Gumleaf Boots, USA

As always, check out Always Wandering Art (Website and Etsy Shop), who usually provides the artwork for our episodes!

Works Cited

Bas, J.M., Oliveras, J. and Gomez, C., 2007. Final seed fate and seedling emergence in myrmecochorous plants: Effects of ants and plant species. Sociobiology, 50(1), pp.101-111.

Caut, S., Jowers, M.J., Cerda, X. & Bouolay, R.R. 2013, "Questioning the mutual benefits of myrmecochory: a stable isotope-based experimental approach: Is always myrmecochory a benefical mutualism for ants?", Ecological Entomology, vol. 38, no. 4, pp. 390-399.

Fokuhl, G., Heinze, J. & Poschlod, P. 2012, "Myrmecochory by small ants – Beneficial effects through elaiosome nutrition and seed dispersal", Acta Oecologica, vol. 38, pp. 71-76.

Lengyel, S., Gove, A.D., Latimer, A.M., Majer, J.D. & Dunn, R.R. 2010, "Convergent evolution of seed dispersal by ants, and phylogeny and biogeography in flowering plants: A global survey", Perspectives in Plant Ecology, Evolution and Systematics, vol. 12, no. 1, pp. 43-55.

Patton, M.T., 2014. “Redirecting” the Study of Mutualistic Benefits To Plants In Myrmecochory.

Türke, M., Andreas, K., Gossner, M.M., Kowalski, E., Lange, M., Boch, S., Socher, S.A., Müller, J., Prati, D., Fischer, M. and Meyhöfer, R., 2011. Are gastropods, rather than ants, important dispersers of seeds of myrmecochorous forest herbs?. The American Naturalist179(1), pp.124-131.

Tarsa, C., McMillan, A. and Warren, R.J., 2018. Plant pathogenic fungi decrease in soil inhabited by seed-dispersing ants. Insectes sociaux, pp.1-7.