Why Evolution is True is a blog written by Jerry Coyne, centered on evolution and biology but also dealing with diverse topics like politics, culture, and cats.
Today we have the life of a butterfly, with photos by Mary Rasmussen. Mary’s captions are indented, and you can enlarge the photos by clicking on them.
The Red Admiral Butterfly
I always leave a few Stinging Nettle (Urtica dioica) plants in my garden here in the Upper Peninsula of Michigan. The Nettles are popular with the Red Admiral Butterfly (Vanessa atalanta) but also feed a variety of other moth and butterfly caterpillars.
Like many Monarch butterflies, Red Admirals are migratory. Most northern Red Admirals are thought to migrate south each fall, but some may overwinter. Red Admirals do not survive the coldest winters and most of North America is re-populated by southern butterflies migrating north in the spring. They are a very welcome sight here in mid-spring:
Female laying an egg. The butterfly’s reproductive organs are located near the lower tip of the abdomen. You can see the tiny green egg that she will deposit on a Nettle leaf. The egg’s surface has a glue that will hold it on the leaf:
Macro shot of a Red Admiral egg on a Stinging Nettle leaf. You can see the hollow stinging hairs of the Nettle leaf. I’ve learned that I can grasp the plant while moving my hand upwards and not suffer any consequences. Moving your hand down along the plant is definitely not recommended.
Caterpillars feed primarily on plants in the Nettle family (Urticaceae). They sew a leaf closed around them to make a protective nest and then eat their way out. They do this several times while they are maturing:
The caterpillar hangs down and forms a “J” shape, signalling that it will soon pupate.
The chrysalis:
The newly emerged butterflies have brilliant coloration. Their underwings are particularly beautiful:
I use a Nikon D500 camera with Nikon VR 105mm f/2.8G macro lens. For the butterfly egg I used a Laowa 25mm f/2.8 2.5-5X Ultra Macro lens with extension tubes.
This guide has an index of the caterpillars and most useful is the index of food plants. Many times I have been able to identify a caterpillar by looking up the plant it is munching.
Doug Hayes, of “Breakfast Crew” fame and also a photographer of dancers, favors us today with photos of a bird rarely seen in his parts (Richmond, VA). His captions are indented and you can enlarge the photos by clicking on them.
Word recently went out over the local birding web sites and Facebook groups that a limpkin (Aramus guarauna) had been sighted in Three Lakes Park and Nature Center, located about ten minutes outside of Richmond. Naturally, this mobilized the Bird Nerds. At any given time, there were ten or more of us photographing the bird. Limpkins are tropical wetlands birds whose territory covers South and Central America and extends northward into Florida. [See range map at bottom.]
The birds spend much of their time probing the water and mud for shellfish and other aquatic invertebrates. This specimen found and ate several large freshwater mussels as we watched. With food this plentiful, the bird will probably linger in the area until the weather turns cooler. Of concern is that limpkins have little fear of humans and on several occasions this one has walked very close to people and sometimes wandered around the parking lots. Hopefully, people will respect the animal and not harm it.
The limpkin wandering along the edge of a stream in search of food. Totally unafraid of people, it actually walked between two of the photographers photographing it:
Doing a bit of preening after a successful hunt for mussels:
Enjoying a good scratch:
Back on the hunt:
Stretching:
More preening:
Eureka! A large freshwater mussel!:
After finding the mussel, the limpkin carried it out of the shade and into the harsh morning sunlight, so the pictures are not so good here. It made quick work of opening the shell:
And even quicker work plucking the mussel from the shell:
Enjoying the feast!:
Here’s the limpkin’s ange map from the Cornell Site All About Birds. They are nonmigratory, so this is their year-round range. The map adds, “Not migratory but dispersing individuals are occasionally found far from range, especially during severe drought.” Doug’s bird was very far from home!
Camera info: Sony A7RV camera body, Sony FE 200-600 lens + 1.4X teleconverter, iFootage Cobra 2 monopod, Neewer gimbal tripod head. I did not have to use digital zoom as the bird stayed so close most of the time
Today we have insect photos by regular Mark Sturtevant. Mark’s captions are indented, and you can enlarge his photos by clicking on them.
Here are more pictures from the previous summer. All were photographed near where I live in eastern Michigan, and most come from a single park about a two-0hour drive to the south of me.
In the woods of this park, there were many of these interesting caterpillars on the ground vegetation. I believe they are the larvae of the Red Admiral Butterfly (Vanessa atalanta), which has been a challenging species to photograph. On a return visit, I would like to bring some back to raise since I’ve never been completely satisfied with my pictures of the adults:
The woodland trail followed a lovely river, and periodically the woods would open up into a meadow. At one such riverside meadow was a stand of interesting flowers (maybe wild mint?) being worked over by the large black butterfly shown in the next 2 pictures. This was for me one of the most exciting finds of the whole summer! This, people, is the melanistic form of the Eastern Tiger Swallowtail Butterfly (Papillio glaucus). I swear this is the same species as the familiar black and yellow swallowtail! This dark form is always female, identified by the splash of blue on the hind wings. The melanistic Tiger Swallowtail is not recorded where I live, but it becomes more common to the south, via natural selection, because there it starts to overlap with the toxic Pipevine Swallowtail which it resembles. But only females can pull off the mimicry trick for some reason. Anyway, I was pretty much hyperventilating while taking these pictures. From the ventral view you can still see the faint Tiger Swallowtail stripes:
JAC: Species in which females mimic another toxic form but males keep the ancestral pattern are far more common than the reverse. Can you guess why males don’t evolve to change their pattern? I’ll put the answer in the comments later.
Turning up tree leaves hanging over a forest trail will commonly reveal something of interest. One leaf along this riverside trail had this weird Derbid Planthopper (Anotia uhleri). I am sometimes asked about the yellow thingies below the eyes of this insect. Those are the antennae, which tend to be oddly distinct in this group of planthoppers:
Another thing that one can find under leaves are insect eggs or recently hatched insects. Here is a group of Leaf-footed Bug hatchlings (Acanthocephala sp.), staying close together to amplify their colorful advertisement that they are chemically protected. Whenever I find these groups, I have to take a deep breath and just do my best. Step to one side, prepare the camera for an extreme close-up, and do some test shots on a random leaf to figure out the correct exposure. Then lift up the leaf again and frantically fire away as the nymphs scamper off:
Along the river bank of the park were some sandy areas, and on the sand were quite a few of these well camouflaged insects. This is a young Big-eyed Toad Bug (Gelastocoris oculatus), which are aptly named predatory Hemipterans that are entirely invisible until they hop:
Here are a couple more finds. This tiny beetle, about the size of a sesame seed, is the Basswood Leaf Miner, Baliosus nervosus:
And the unsavory face in the next picture actually belongs to a rather cute and mild-mannered Two-spotted Tree Cricket, Neoxabea bipunctata:
I’m not always sure which critter in this set was from that distant park that I mentioned. But this one sure was! There, I was delighted to find this large katydid known as the Common True Katydid (Pterophylla camellifolia), which is another insect that does not occur in my area. Despite their large wings, True Katydids are flightless. At dusk, this male will begin its song; with some imagination, it is described as sounding like: “Katy did! Katy did !! She didn’t! She did !!!” Readers who live in its range will know it well, as they can be fairly deafening. Here is one singing. If it doesn’t hurt your ears a little, you aren’t playing it loud enough:
And finally, for the heck of it, here is what I believe is a Northern Leopard Frog (Lithobates pipiens) although there is also the similar species called the Pickerel Frog. The two differ in the form of their spots plus some other details. We see some colorful frogs from far-off places on this website, but this domestic one is still quite lovely, I think:
Today’s photos come from ecologist Susan Harrison at UC Davis. Her captions are indented, and you can enlarge the pictures by clicking on them.
Southeastern Arizona (part 1)
Sooner or later, a U.S. birdwatcher must go to Southeastern Arizona. That’s because dozens of Mexican and Central American bird species make it just across the international border into the tree-lined canyons of Arizona’s Chiricahua Mts., Huachuca Mts., and other small north-south oriented mountain ranges. Many of these birds are as dazzlingly colorful as you’d expect from their mainly tropical and subtropical distributions.
In August 2023 I made my pilgrimage to see these species. Today I’ll show the most localized species, and next time I’ll show some of the ones that also range east into south Texas, west to the California deserts, and/or north to the Great Basin deserts.
First, a habitat shot of a canyon in the Chiricahua Mts.:
Next, the region’s most fabled bird, the Elegant Trogon (Trogon elegans):
Hummingbird diversity is perhaps the region’s greatest claim to fame besides Trogons. Over a dozen species can be regularly found here! The technique for seeing them is to visit small eco-lodges and visitor centers where feeders have been set up. Here are four species:
Some Southeastern Arizonan birds are close southern relatives of birds that are familiar elsewhere in the U.S. Here are four examples:
Mexican Jay (Aphelocoma wollweberi), almost identical to California Scrub Jay (Aphelocoma californica) but more social in its behavior; we always saw them in flocks:
Mexican Duck (Anas diazi) in front of a Mallard (Anas platyrhynchos); these two species often hybridize in urban settings like this Tucson pond:
Whiskered Screech-Owls (Megascops trichopsis), related to Western Screech-Owls (Megascops kennicottii) and living beside them in this area, but in slightly drier habitats:
Mexican Spotted Owls (Strix occidentalis lucida), found in pine and fir forests at higher elevations, closely related to and just as threatened as the Northern Spotted Owl (Strix occidentalis caurina). This roosting pair is grooming each other’s facial feathers. My title for this photo is “Get a room, owls!”:
It’s Sunday, and John Avise is here with another batch of themed bird photos. The theme this week happens to be a place that I just visited! John’s captions are indented, and you can enlarge his photos by clicking on them.
A Few Galapagos Birds
In recognition of Jerry’s recent trip to the Galapagos Islands, this week’s post consists of a few Galapagos birds that I photographed on my own trip to the Galapagos Islands back in 2005. This was at a time before I became seriously interested in avian photography, and I had only a cheap little camera. But many Galapagos birds are so tame that I still managed to get a few decent photos. Now I’d really love to go back to the Galapagos with my good camera and more of an avian photographer’s eye!
I’m gratified that several readers sent in sets of photos, so we’re set for at least four or five more days. This batch comes from reader James Blilie, whose captions are indented. You can enlarge the photos by clicking on them.
Here are some landscape shots for your consideration. Most of these are taken on or near our homestead in Klickitat County, Washington.
Wintertime shot of our neighbor’s vineyard (wine grapes) in White Salmon, Washington. Iphone 11 photo.
A shot from last fall using my MEKE 3.5mm f2.8 220 Degree Manual Focus Circular Fisheye Lens: Ponytail Falls in the Columbia River Gorge. I enjoy fisheye lenses. They help me reimagine images.
Rain drops. Winter 2023.
Frost on charcoal. Winter 2023.
A view westwards into the Columbia River Gorge. Very close to our home.
Falls Creek Falls, about 280 feet tall. Washington side, near the town of Carson.
We recently traveled to our old stomping grounds in the US Midwest. As Jamie said, when we arrivedin the heat and humidity, “I forgot how great the weather is in White Salmon!” These are photos of sunflowers in Shawano County, Wisconsin.
Our son Jamie is just starting his engineering education as Washington State University, in Pullman, Washington (Go Cougs!). On the weekend we moved him into his dorm, we went out into the Palouse to make photos of the unique landscape. Whitman County, which covers a large area of the Palouse, produces more wheat than any other county in the USA. These images show wheat being harvested, The unusual fluid shape of the Palouse hills, and a short depth of field shot of wheat ready for harvest.
Finally, my ringer. Jamie and me on top of a local prominence, Chinidere Mountain with Mount Hood in the background. Taken with my circular fisheye lens.
Equipment:
iphone 11
Olympus OM-D E-M5 camera (Crop factor = 2.0)
LUMIX G X Vario, 12-35MM, f/2.8 ASPH. (24mm-70mm equivalent, my walk-around lens)
LUMIX 35-100mm f/2.8 G Vario (70-200mm equivalent)
LUMIX G Vario 7-14mm f/4.0 ASPH (14-28mm equivalent)
MEKE 3.5mm f2.8 220 Degree Manual Focus Circular Fisheye Lens
LUMIX G Vario 100-300mm F/4.0-5.6 MEGA O.I.S
Today we have part II of Athayde Tonhasca Júnior’s perambulations through the Greek city of Thessaloniki (part I is here). His captions are indented, and you can enlarge the photos by clicking on them. I received one additional batch of photos from another reader, but if I don’t get more, tomorrow the well runs dry. Please send in your pix!
Walking the Streets of Thessaloniki, part II
A replica of one of the relief figures comprising Las Incantadas (The Enchanted Ones), a group of ancient pillars from 2nd or 3rd AD. Nobody cared much for the monument (Ottoman soldiers supposedly took pot shots at it for target practice) until the Turkish governor sold it to the French consul in 1864. The Frenchmen’s shoddy work in removing the massive monument, breaking it in several places, almost caused civil unrest: crowds of Greeks, Jews and Turks tried to prevent its embarkation, but in vain: today the restored Incantadas reside in the Louvre. Greece tried to get them back in recent times, but the French position was certainement pas. They sent this replica instead (paid by the Greeks) to the Archaeological Museum. The name Las Incantadas comes from Ladino, the old Spanish language brought to Thessaloniki by Sephardic Jews after they were booted out of Spain. Ladino, or Judeo-Spanish, is sprinkled with Portuguese, French, Hebrew and other sources, and was once Thessaloniki’s main lingo: today it is basically extinct in the city – not surprising, as about 90% of its Jewish population was killed during the war – and endangered elsewhere:
A painting in the War Museum depicting a group of Greek guerrillas led by Konstantinos Kanaris, a national hero, sneaking away after one of the Greeks’ special tricks during the war of independence (1821–1829): to board a Turkish ship in the middle of the night and set it alight. The American and South American wars of independence were gentle affairs when compared to Greece’s struggle to be liberated from the Ottoman Empire. The level of atrocities, from both sides, is hard to comprehend. Decapitation, rape and enslavement were the destinies of villagers taken by the enemy´s side (for a hair-raising and excellent account of the revolution, see Mark Mazower’s The Greek Revolution: 1821 and the Making of Modern Europe):
You can’t get away from history in Thessaloniki. Excavation work in the 5th-century Byzantine church of Panagia Acheiropoietos (another UNESCO site) brought to light segments of a flooring from a Roman bath used by early Christians (2nd-4th c.):
In another corner of the church of Panagia Acheiropoietos, Sultan Murat II reminded the masses who’s the boss: ‘Sultan Murat Conquered Thessaloniki in 833’ (1430 in the Christian calendar). After a 8-year siege, Thessaloniki was taken by the Ottomans and remained in their hands for the next five centuries, until it became part of the Kingdom of Greece in 1912:
The impressive wall enclosing Thessaloniki’s centre. It was built in stages by the Romans, then early Christians (4th to 5th c.). If you were caught outside at night, too bad: the gates were locked and nobody could enter or exit until next morning:
In the 5th c., a magistrate named Ormisdas was praised for his honest handling of public funds used for renovation works at the wall. This inscription reads: “With unsoiled hands Ormisdas built these impregnable walls and made the city great”. Clean-handed Ormisdas types are in short supply in Greece nowadays: Transparency International ranks the country higher than Hungary and Italy in their Corruption Index, which is quite a feat:Like many other churches in town, the Church of Saints Constantine and Helen doesn’t look impressive from the outside. Once you get in, you are overwhelmed by artistic details. St Constantine is the very same Constantine the Great, Roman emperor who is believed to have ordered the execution of his eldest son and his second wife. A character of mixed reviews in the East and West:
Loutra Paradisos (Paradise Baths), constructed by Sultan Murad Il in 1436 or 1444 at the location where there may have been a complex of imperial baths during the Roman era. There were male and female bath sections:
The Arch of Galerius, built in the years 298 and 299 AD to celebrate Galerius’ victory over the Persians, Rome’s enduring enemies:
About 1/3 of Thessaloniki was wiped out by the big fire of 1917. Out of the ashes, splendid buildings like this one replaced the old houses in the city centre:
A few generous readers sent in photos, so we’ll have some today and tomorrow. In the meantime, please put together some photos for my return after August 20, as I’ll have only one batch left then. Thanks!
Today we have another installment of The Breakfast Crew photographed by Doug Hayes of Richmond, Virginia. Doug’s captions are indented and you can enlarge his photos by clicking on them. Today he returns to the swamp to check on the progress of the baby green herons (see here for part I)
More of the Breakfast Crew.
Grackles and mourning doves are the most active right now. The usual house finches and sparrows are present and there has been a population explosion of cardinals. I also took another trip out to the Chamberlayne Swamp to see how the baby green herons are doing.
Robins (Turdus migratorius) are almost always around the yard. They almost always go for the suet instead of the birdseed:
A pine warbler (Setophaga pinus). These little guys tend to stick to the more wooded areas of the park and along the James River:
Most people consider common grackles (Quiscalus quiscula) to be pests, but I think they are gorgeous with their iridescent feathers and intense eyes:
A male northern cardinal (Cardinalis cardinalis). There has been a population explosion among these birds this season. In addition to the adults, there are quite a few fledglings in the yard:
A non-breeding/immature male red-winged blackbird (Agelaius phoeniceus). Red-winged blackbirds are marsh dwellers, but they tend to show up in large numbers after heavy rains:
And a breeding male, showing off his wing patches:
A male house finch (Haemorhous mexicanus) looking spiffy:
A male red-bellied woodpecker (Melanerpes carolinus) finds a peanut. They are quite persistent in digging around in the feeder until they find their favorite treat:
A gray catbird (Dumetella carolinensis). I haven’t seen many of these birds this season. They used to feed on blackberries that grew in my neighbor’s yard, but the bush was cut down when the house sold a few months ago:
A tufted titmouse (Baeolophus bicolor). These little guys also love peanuts. Like the woodpeckers, they grab a peanut and fly off with it to eat in the safety of the trees:
A juvenile European starling (Sturnus vulgaris). For some reason, starlings are not as numerous this year as they have been in the past:
We went back to the Chamberlayne Swamp Saturday morning to check on the progress of the baby green herons (Butorides virescens). The four babies are about a month old and all are thriving, even the runt. All four are nearly adult size and have lost most of their fuzzy down. They spend their days climbing around the nest tree, chasing dragonflies and being fed. As usual, the Big Guy stations himself out in the open so he can be the first one fed when mom returns. All four should head out on their own soon:
The Big Guy keeping a watch for mom:
The rest of the gang:
The Big Guy hunting dragonflies. He managed to catch a few while we watched:
Camera info: Sony A7RV mirrorless camera body, Sony FE 200-600 lens + 1.4X teleconverter, Clear View digital zoom, iFootage Cobra 2 monopod, Neewer gimbal tripod head.
Thank Ceiling Cat: two readers came through with photos when the tank was empty. Today’s lot comes from Leo Glenn, who sends photos from Costa Rica. His captions are indented, and you can enlarge the photos by clicking on them.
Here are some more photos from my recent trip to Costa Rica.
There are four species of monkeys in Costa Rica: the Central American squirrel monkey (Saimiri oerstedii), the Panamanian white-faced capuchin (Cebus imitator), Geoffroy’s spider monkey (Ateles geoffroyi), and the mantled howler monkey (Alouatta palliata). As we were spending most of our time in parks and nature preserves, we were hopeful that we would see at least one of the species. It came as quite a surprise to us, then, that while we saw no monkeys in any of the nature preserves, a family of mantled howlers moved Into the trees next to our rental house and spent around 45 minutes eating, lounging, and playing. It was an amazing experience.
Like cats, they were masters at relaxing in the most precarious of positions.
We enjoyed watching them use their prehensile tails to move among the branches, sometimes hanging from them to reach the choicest leaves, which make up 75% of their diet.
Another species that we were hoping to catch a glimpse of was a coatimundi. And just as we pulled into the Monteverde Cloud Forest Reserve, a South American coatimundi (Nasua nasua) strolled right across the parking lot.
Coatimundis, known locally as pizotes, are members of the family Procyonidae, the same family as raccoons, and they share many of the same traits. Unlike the more nocturnal raccoons, however, coatimundis are diurnal.
In the cloud forest, we came upon a nest of red-tailed stingless bees (Trigona fulviventris). Our guide said that the honey they produce is inedible, but it has been used traditionally for medicinal purposes. I couldn’t find any information on that, but I did read that the sticky resin they make to build their nests has been used by fishermen to caulk leaks in their canoes. Another occasion when I wished I had a longer lens.
A tree fern (Cyathea holdridgeana). I was particularly excited to see this, as I have been obsessed with paleontology since I was a child. Tree ferns, along with Lycopods and Horsetails, were the predominant “trees” in ancient forests, before our current trees evolved. This particular species grows at elevations of 2400-2800 m, much higher than most other tree ferns in Central America. I believe we were at around 2100 m on this tour.
A colorful group of caterpillars. I was unable to determine the species, but they appear to be a moth in the genus Euglyphis.
And finally, our rental house came with a cat [Felis catus], whose name was Linda.
Linda asking to be let in.
Below: Linda’s favorite activity, after we let her in (other than begging for something to eat). She was 17 years old, and growing deaf. Her meow was loud enough to wake the dead (something she liked to do at five in the morning outside our bedroom window). But she was otherwise spry and hale. Of course we fell in love with her.
Well, folks, this is the last substantive batch of photos I have in the tank. If you want more this week, you’ll have to provide them. These come from our most regular regular, Mark Sturtevant; his captions are indented and you can enlarge the photos by clicking on them.
This post has been on my mind for several years, beginning with an encounter that I had with a weird little fly on a bridge. Here is that fly (I think Pseudotephritina sp.), and I had probably shared it here once upon a time. It was marching up and down on the bridge rail while continually waving its wings. I did my best to photograph the little insect, which was no bigger than a fruit fly, with my little 50mm lens on extension tubes. But I wasn’t the only one interested in the fly. There was also a jumping spider, and it definitely was intent on having the fly for a meal! As the spider stalked closer, the fly would suddenly turn to it, waving its wings, and the spider would flee! This was repeated several times until the spider gave up. Did the stripes on the wings look like spider legs to the jumping spider? Jumping spiders do signal to each other by waving their legs. This is how they avoid conflict.
Now one must not make too much of this impression from a one-time encounter like that. But many flies in several different families have boldly patterned wings which they wave around. While this is known to act as intraspecific communication, it is thought that in at least some species flies also use this kind of display to scare off free-roaming spiders like keen-eyed jumping spiders. There is, for example, a classic paper concluding that another fly, Rhagoletis zephyria, would frequently display its patterned wings when stalked by jumping spiders, and spiders would tend to stop their approach in response. Here is a picture from that study, and one can definitely see that the fly does look like a jumping spider:
R. zephyria is part of a large species complex of flies that all strongly resemble each other. From the BugGuide web site, I count 18 species in North America. One of these is the apple maggot fly (R. pomonella), and I do have two apple trees and I see what I presume is that species of fly in the yard from time to time. It should be mentioned that the apple maggot fly is also a classic example of sympatric speciation, since the flies originally relied on hawthorn trees as their host. [JAC: the idea that the two host races of this fly formed sympatrically is probably not correct; see Coyne and Orr 2009). But with the introduction of apples into the country, some of them jumped to apple trees and there is now significant reproductive isolation between the two populations. Anyway, one of the flies appeared on my back porch last summer, and because I was able to catch it I could at last act on what has been on my mind for many years. Would this fly use its wings to deter a jumping spider? Mind you, this is a different species from the one described above, but … maybe? The following pictures record the results of this admittedly informal attempt to test that hypothesis.
Here is the fly, feeding on slices of sour green apples. It was quite content to just sit there and feed since I had starved it for a day.
Now when this fly turns away from the camera, one can certainly see that its wing markings are very much like spider legs. Both males and females display their wings when encountering one another, but what would happen if I introduced a jumping spider?
So out to a local field I went, and soon returned with a test subject—a handsome male Phidippus clarus[see citation below]. What would happen if the two met? Would the fly react to the spider? Would the spider react to the fly (other than making a meal of it)?
In my arena I had the fly, feeding away, and the spider was kept several inches away under a clear plastic cup. When the spider was facing the fly, I would then lift the cup and make ready with the camera. After about 10 tries (I should have counted, but I didn’t), I could definitely say: I am not sure! Most times the spider did look at the fly, and sometimes it paused to look at it, as it was doing here for some seconds. But then it would turn and walk away. At no time did it stalk the fly, nor did it hustle off like it was fleeing. So I can’t “read” what the spider saw of the fly other than that it wasn’t prey.
Meanwhile, the fly just kept feeding, and it did not seem to react to the spider at all. But on one occasion – just one! – the fly certainly did seem to react to the spider by suddenly spinning around (it was facing away before), and it held out its wings. Here is that moment, with the fly out of focus in the background.
And here is a second picture, now focused on the fly. That is not a relaxed posture. The spider for its part just paused briefly, and then moved away.
I don’t know what to say about this informal experiment, other than that the one response from the fly encourages me to try it again. I am currently keeping an eye out for more of the flies.
As a kind of postscript, there is this lovely paper which proposes that many species of insects from several different orders may be mimicking jumping spiders to ward off predation. There are lots of cool and enticing pictures, and the readers here will certainly enjoy having a look.
