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We often see recommendations for summer reads, and although it isn't lightweight (hardcover at 328 pp), the new book  Amazing Arachnids by Jillian Cowles makes my list.

The American Southwest is full of interesting and unique arachnids. In this book, naturalist and clinical microbiologist Jillian Cowles has captured photographs over over 300 different kinds of arachnids from eleven orders found there, including some that have never been seen before. (The cover photo is by Bruce D. Taubert).

Of course we looked for ants first. They are not listed in the index, but there's a photograph of a tiny ant mimic spider in the genus Bellota on page 29. Cowles mentions that black widow spiders eat ants (page 200) and has a full page photograph of Euryopis scriptipes spider holding a harvester ant on page 201. On page 245 is a Peckhamia jumping spider that mimics ants and on page 253 there are three genera of ant mimic spiders, Tutelina, Sarinda, and Peckhamia again.

In addition to spiders, the book covers:

  • Scorpions
  • Psuedoscorpions
  • Vinegaroons
  • Short-tailed Whipscorpions
  • Tailless Whipscorpions
  • Microwhipscorpions
  • Harvestmen
  • Wind Spiders
  • Ticks and Mites

Cowles passion comes through in the text. She discusses anatomy and taxonomy for each group before delving into their unusual biological characteristics. For example, she suggests the ability of scorpions to fluoresce at night under UV light may "reflect" a way they protect themselves against the intense daytime solar radiation of the desert Southwest. Cool!

If you are as fond of or fascinated by all things eight legged as Cowles, then Amazing Arachnids is the book for you.

Hardcover: 328 pages
Publisher: Princeton University Press (June 12, 2018)
ISBN-10: 0691176582
ISBN-13: 978-0691176581

Know any children who are interested in spiders? Try one of these two adorable fiction picture books with spider characters.

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.

There's a question for the Consult-Ant this week. (The “Consult-Ant” started on the Leaping from the Box website, where I answered questions about ants and ant farms. From now on I will post the answers here, and when Karen has time she will also post the answers on her site.)

Question:  I have an ant question!
I have been observing common ants foraging and wonder what range their senses have to understand their foraging tactics. Presumably they are hoping to discover a food source.
Mike.

Answer:

Wouldn't it be cool to be able to slip into a creature like an ant and experience the world through their senses?

Unfortunately, we aren't quite there yet. Scientists are making some breakthroughs in understanding how ants perceive the world, but there are still many, many questions. To make things even more complicated, it appears that different species of ants have different sensory abilities, so there isn't just one answer as to how ants' senses work.

Although ants have a variety of senses, most ants probably use a combination of vision and olfaction to find their food. Let's explore those two in more detail.

1. Vision

Without even knowing how ants' eyes work, we can see there are big differences in the structure.

For example, this ant has massive eyes.

(Gigantiops destructor Photographer: Michael Branstetter Date Uploaded: 07/20/2009 Copyright: Copyright AntWeb.org, 2000-2009. Licensing: Attribution-ShareAlike 3.0 (cc-by-sa-3.0) Creative Commons License)

This huntress has normal-sized eyes.


Army ants have reduced eyes or are even blind.

(Public domain photograph of Eciton burchelli by Alex Wild)

For ants with well-developed eyes, we would expect that since they are small and close to the ground, perhaps they can't see far. In fact, (2004) found Myrmica sabuleti ants could discriminate objects 15 cm away, but only 10 cm above. On the other hand, bulldog ants in the genus Mymecia have excellent vision and have been reported to be able to see a meter away.

How do ants use vision for foraging? Not only can they spot prey, but also according to Hölldobler and Wilson (1990) foraging worker ants can learn/remember to return to places where they found food in the past using visual cues. Researchers have found some species of ants can orient to food sources using the the skyline (Graham and Cheng, 2009), or polarized light (for example Krapp 2007, Wehner et al. 2014). So, they may see farther than we might expect.

Related:

2. Sense of smell - Olfaction

Blind ants -- or those that forage at night -- may use their sense of smell to find food. Insects detect odors largely with their antennae.

How do the antennae work? Within the antennae are odor receptors that can bind with specific free-floating molecules. When the correct molecule bumps into and binds with the receptor, a nerve associated with it sends a signal to the mushroom bodies in the insect's brain, where it is processed or identified.

From how far away can ants detect smells? It really depends on how far the odor molecules can travel. I wasn't able to find much about detection distances for ant antennae, but male moth antennae can detect female moth pheromones from 300 feet away.

What kinds of things can they smell? Zwiebel at al. (2012) found over 400 different odor receptors in each of two species of ants: a carpenter ant, Camponotus floridanus, and the Indian jumping ant, Harpegnathos saltator. Using an unusual bio-assay involving frog eggs they discovered that although the receptors were equally numerous in both species, the odors detected by the receptors were not the same. For example, the jumping ant could detect a component of anise (a spice), whereas the carpenter ant could detect an odor from cooked pork. Presumably those differences reflect differences in their biology or environment.

According to the same article, ants also have gustatory receptors, which distinguish taste (among other things). In addition, they have ionotropic glutamate receptors that can detect toxins and poisons. This can be important for seed-harvesting ants and leaf cutter ants because plants may contain toxins that will either harm the ant larvae, or the fungus that leaf cutter ants garden for food.

3. Scouting for Food?

"Presumably they are hoping to discover a food source."

Yes, when they are outside the nest, by-and-large foraging ants are looking and smelling for food. (Although a few may be scoping out potential enemies as well.)

Again, the process varies depending on what kind of ant you have. Some ants are solitary hunters. Each ant hunts and brings food back on its own, whether seeds or insect prey. In some species, special scouts search for food and return to the nest once they find it. They recruit other foragers to retrieve the food. Often the strategy will be intermediary, and depend on the size or quantity of food on a given day.

Although most ants are omnivores, what constitutes food will also vary and those differences will change how ants detect it. For example, ants that tend aphids or leafhoppers may locate potential food by smelling honeydew that has dropped to the ground under the plant where the insects are feeding.

Conclusion

The bottom line is that how an ant finds food will be limited by the range of its senses, but right now we don't have a complete picture of what those limits are. Personally, I would not be surprised if we discover that certain ants have some amazing abilities that we haven't even thought to look for yet.

_________

Hopefully, that answers your question at least in part.

Does anyone else have anything to add to help Mike?

National Pollinator Week 2018 starts today.

Let's start the celebration by taking a look at a new book, Butterfly Gardening: The North American Butterfly Association Guide by Jane Hurwitz.

Why feature butterfly gardening on an ant blog? Butterfly gardening encourages the use of native plants, which supply flowers that are used by many different pollinators as well as butterflies. The leaves and seeds are food for caterpillars, plus other insects that support food webs. Butterfly gardening is win-win!

As for the book, the first part features basic information about common garden butterflies, their life cycles, and their needs. Range maps are included so you can find out which species of butterflies to expect in your area and what some of their common caterpillar food plants are.

Because the recommended species of butterfly garden plants vary depending on where you live, in Part II members of the North American Butterfly Association suggest flowering plants and trees specific to regions around the United States, from the Florida to Portland, Oregon.

Overall, the book is illustrated with gorgeous, captivating photographs. It is also packed with tried-and-true practical information from experienced butterfly experts.

Butterfly Gardening: The North American Butterfly Association Guide is a fantastic resource. Be inspired by a copy today.

Check out some previous posts on the same topic:

Do you have any suggestions for plants that are good for pollinators and/or ants?

Flexibound: 288 pages
Publisher: Princeton University Press; Flexibound edition (April 10, 2018)
ISBN-10: 0691170347
ISBN-13: 978-0691170343

Disclosure: This book was provided by the publisher's representative for review purposes. Also, 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.

A few ant nests dot the sides of a walking pathway at a nearby park, so of course I have to check them out.

For the most part the nests are small colonies of southern fire ants, Solenopsis xyloni.

There are also seemingly endless streams of Forelius mccooki workers traveling along the concrete edgers and sidewalks.

While taking photographs of the fire ant middens, I noticed the fire ants had a few visitors standing by an entrance hole.

Millimeters away from the fire ant workers stood two Forelius workers.

 

Curious, I watched for some minutes. The fire ants did not approach the Forelius, and the Forelius remained relatively still. They didn't appear to be investigating the middens.

The Forelius had a nest entrance not too far away. Perhaps they were just nosy neighbors? (I did notice there weren't any Solenopsis visiting them.)

Wayne Armstrong suggests perhaps the relationship isn't entirely benign. In this video, Solenopsis xyloni workers flag their gasters in response to Forelius pruinosus workers encountered at an artificial feeding site. (You will notice the coloration difference between our local S. xyloni compared to his California ones.)

Interestingly, the soldiers don't seem to respond. According to his notes (scroll down to Southern fire ant), the Forelius were ultimately successful in overtaking the food.

Ants of the Southwest has a photograph of a Forelius worker spraying a S. xyloni worker. He reports S. xyloni exoskeletons piled in Forelius middens, which is also reported here.

Even though southern fire ants are chemically well defended, perhaps they are no match for Forelius.

Have you ever encountered these two species?

References:

Obin, Martin & Vander Meer, Robert. (1985). Gaster flagging by fire ants (Solenopsis spp.): Functional significance of venom dispersal behavior. Journal of chemical ecology. 11. 1757-68. 10.1007/BF01012125.