Just in time for the summer firefly season comes a new popular science book, Silent Sparks:  The Wondrous World of Fireflies by Sara Lewis.

Most of us probably remember the wonder we experienced the first time we saw a firefly light up a summer night. Sara Lewis has captured that amazement in a bottle and poured it out onto the page.

Lewis's passion about her topic shines through from the first paragraph. Written for the lay reader and scientist alike, she summarizes what we know about fireflies from scientific research, but uses easy-to-understand language and defines all the terms, even including a glossary in the back matter. For example, she explains glow-worm fireflies are not worms or larvae at all, but are "plump and wingless females" that glow to attract males.

Most readers probably know fireflies are really beetles. Did you also know not all members of the firefly family (Lampyridae) light up? Lewis calls lampyrids that fly during the day and don't light up "dark fireflies." Without the ability to flash, dark fireflies attract mates via pheromones.

Other topics covered in the book include how fireflies produce the glowing light and how it has been exploited in tests for the presence of ATP. She explains what larval fireflies look like and discusses why those that glow do so for a different reason than the adults. She writes extensively about firefly reproduction, the topic of her own research. Lewis also includes practical firefly wrangling advice, ranging from how to get a firefly to sit still (give it a bit of apple) to how to encourage fireflies in your neighborhood (tone down the outdoor lighting). In the back is a key and a field guide to North American genera of fireflies.

Silent Sparks is an enlightening book about these fascinating insects. Reading it just might inspire you to go outside and spend a summer night contemplating the wonder of fireflies.


Firefly Watch Citizen Science

Want a glimpse into the flavor of the book? Check out the author's TED Talk, Sara Lewis: The loves and lies of fireflies

Princeton University Press also has a chapter to download and read.

Hardcover: 240 pages
Publisher: Princeton University Press (April 26, 2016)
ISBN-10: 0691162689
ISBN-13: 978-0691162683


Illinois, USA.
(Public domain photograph of Photinus sp. firefly by Alex Wild)

Disclosures:  This book was provided by the publisher for review purposes. I am an affiliate with Amazon so I can provide you with cover images and links to more information about books and products. As you probably are aware, if you click through the highlighted title link and purchase a product, I will receive a very small commission, at no extra cost to you. Any proceeds help defray the costs of hosting and maintaining this website.

The human gut microbiome, what microorganisms might be found in our digestive systems and what roles those microorganisms have, has been in the news lately (see the National Microbiome Initiative). The human studies build on research on other organisms such as cows and termites, which have long been known to have archaea, bacteria, and protozoa in their digestive tracts to aid in the digestion of cellulose. What about our favorite creatures, ants? Do they have any gut microsymbionts?

Cepalotes-clypeatus-turtle_ant-Alex-Wild-public-domain(Public domain photograph of Cepalotes clypeatus turtle ants by Alex Wild)

It turns out quite a few species of ants do have endosymbiotic microorganisms in their guts. Studies in the last two decades have shown that ants in the genera Tetraponera, Acromyrmex, Atta, Dolichoderus, Camponotus, Colobopsis, Polyrachis, Echinopla, CephalotesCataulacus, and the ponerine ants Dinoponera lucida, Neoponera curvinodis, Pachycondyla striata, Odontomachus brunneus and Odontomachus bauri have specific bacteria associated with their digestive systems. It is likely more examples will be found as we continue to investigate other genera.

In some cases the ants also have specialized structures associated with the bacteria. For example, some species of Tetraponera have a pouch off the midgut where symbiotic bacteria are housed. Lanan et al. propose the proventriculus (located between the crop and midgut) in some species of Cepahlotes turtle ants acts as a filter to help conserve gut microsymbionts by preventing contamination by other bacteria entering with food. Camponotus ants (and their close relatives) have bacteriocytes, which are cells that house endosymbiotic bacteria of the genus Blochmannia.

Why do ants have gut microsymbionts? As with other animals, the microsymbionts help provide nutrients not accessible by standard digestion, such as vitamins, amino acids, or sterols. Apparently, adult worker ants of many species obtain most of their nutrition from plant fluids, such as directly from nectaries or indirectly from honeydew of insects feeding on plants. Plant fluids are low in amino acids (nitrogen), so the microsymbionts help generate nitrogen sources in exchange for food and a protected environment (Russell, et al.) In fact, Davidson et al. have suggested the presence of gut microsymbionts is what has allowed ants to become so abundant in tropical rainforests.

Seems we have much to learn about how microorganisms are involved in ant digestion and nutrition.

References (links go to journals, most with free .pdf available)

Termite gut microbes

Billen, J., Buschinger, A. (2000). Morphology and ultrastructure of a specialized bacterial pouch in the digestive tract of Tetraponera ants (Formicidae, Pseudomyrmecinae). Arthropod Structure & Development 29: 259-266

Tássio Brito de Oliveira, Milene Ferro, Maurício Bacci, Danival José de Souza, Renato Fontana, Jacques Hubert Charles Delabie, Aline Silva. (2016). Bacterial Communities in the Midgut of Ponerine Ants (Hymenoptera: Formicidae: Ponerinae). Sociobiology Vol 63, No 1 pp. 637-644

Diane W. Davidson, Steven C. Cook, Roy R. Snelling, Tock H. Chua. (2003). Explaining the Abundance of Ants in Lowland Tropical Rainforest Canopies. Science09 May: 969-972

Michele Caroline Lanan, Pedro Augusto Pos Rodrigues, Al Agellon, Patricia Jansma, and Diana Esther Wheeler. (2016) A bacterial filter protects and structures the gut microbiome of an insect
. The ISME Journal advance online publication 12 February: 1-11. doi: 10.1038/ismej.2015.264

Russell, J.A., Moreau, C.S., Goldman-Huertas, B., Fujiwara, M., Lohman, D.J., Pierce, N.E. (2009) Bacterial gut symbionts are tightly linked with the evolution of herbivory in ants. Proc Natl Acad Sci USA 106:21236–21241. doi: 10.1073/pnas.0907926106

Souza, D.J., Bézier, A., Depoix, D., Drezen, M., Lenoir, A. (2009). Blochmannia endosymbionts improve colony growth and immune defence in the ant Camponotus fellah. BMC Microbiol 9:1-8. doi:10.1186/1471-2180-9-29

Last time we discussed how certain species of ants can swim. Even if they can't swim, some species are able to withstand temporary floods by grouping together to form living rafts to float on the water.

Although there has been a rash of papers about the ability of fire ants to form rafts, Jessica Purcell, assistant professor of entomology at The University of California, Riverside, has been studying the ability to float by Alpine silver ants, Forica selysi.


Formica_selysi-worker(Photograph by Estella Ortega / © AntWeb.orgCC-BY-SA-3.0)

After marking some of the worker ants, the researchers subjected the ants to flooding. They discovered that when the same ants were subjected to flooding a second time, many of them assumed the same positions in the rafts. Rather than coming together randomly, as might be expected during a flooding crisis, the ants were apparently assembling in a somewhat organized fashion.

This video shows the experimental protocol. Note: You probably will want to turn down your computer's sound or hit mute before you click on the play button.

Based solely on this video, I'm going to suggest that painted ants tend to be towards the outside of the raft. Is it possible that damaged ants (painted ants) can assess their health and position themselves at the rim?  Of course, that may have happened at random, too. What do you think?


All ants on deck, EurekAlert, AAAS

Purcell J, Avril A, Jaffuel G, Bates S, Chapuisat M (2014) Ant Brood Function as Life Preservers during Floods. PLoS ONE 9(2): e89211. doi:10.1371/journal.pone.0089211

If you have a pool, you know that most insects don't have a chance if they fall into the water. Here at Wild About Ants, however, we know ants often do the seemingly impossible. To prove it, let's look at the ability of certain species of ants to swim.


In a recent article in Myrmecological News, Gora et. al. reported on their investigation into swimming by the carpenter ant, Camponotus pennsylvanicus. They found carpenter ants use vision to find escape platforms from the water. One hundred percent of the control ants placed in the water of the test apparatus were able to swim to the edge and get out of the water successfully. Ants with their vision occluded, on the other hand, failed to exit the water.

Although this study focused on ants swimming as a method to escape from water if they fall in accidentally, some Camponotus ants in pitcher plants are able to actively swim to capture mosquito pupae for food. In this video you can see how they move all six of their relatively short legs to push through the liquid.

As you might expect, ants that live in areas that are regularly flooded by tides, such as ants living in mangrove swamps, are particularly good at swimming.

This video from Life in the Undergrowth shows mangrove ants running across shallow water and then at about 1:02 minutes actively swimming in the water. Notice how the swimming ant holds its hind legs out behind it like a rudder.

Yanoviak and Frederick tested 35 species of tropical forest ants to see how many had the ability to move through water in a directed way. Of those, ten species were able to show rapid directed movements and ten more exhibited slower, but directed movements. The remaining species apparently needed tiny life jackets.

The bottom line is that although different species of ants vary in their ability to swim, some are quite adept at it.

Previous Posts at Wild About Ants:


Gora, E.M., Gripshover, N. & Yanoviak, S.P. (2016) Orientation at the water surface by the carpenter ant Camponotus pennsylvanicus (De Geer, 1773) (Hymenoptera: Formicidae)  Myrmecol. News 23: 33-39. (Let me know if the link doesn't work and I'll find it for you.)

S. P. Yanoviak, D. N. Frederick (2014) Water surface locomotion in tropical canopy ants. Journal of Experimental Biology 217: 2163-2170; doi: 10.1242/jeb.101600