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.
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:
Well, I have exactly one two-part reader contribution left, including today’s post (part I) from Athayde Tonhasca Júnior. But beyond that, the tank is dry. Please send in your wildlife photos. (If you already have but they didn’t appear, please resend them.) Don’t let this feature die!
So, here’s Athayde’s contribution, a portrait of a lovely city whose location in Greece I’ve put below. I spent a few happy days in Thessaloniki while hitchhiking from Athens to Istanbul (after going to the islands and before hitching up through Europe and down to Morocco) in 1973. One story I’ll never forget: my girlfriend and I were staying with an old friend who lived on a farm outside of town. We went to a local taverna and ordered dinner, and then unordered dishes started coming to our table: cucumbers, ouzo, and various foodstuffs. Where did they come from? The mustachioed locals looked at us, smiled, and we realized they were the gift-givers, who surely saw no tourists in the remote establishment. They then put on music and smashed dishes on the floor, a Greek custom when celebrating. It was a remarkable display of friendship to foreigners.
Here’s Thessaloniki, on the route from Athens to Istanbul.
Walking the streets of Thessaloniki, part I
Thessaloniki, founded around 315 BC and named after princess Thessalonike of Macedon, the daughter of Philip II and half sister of Alexander the Great. The princess’ name in turn was a homage to a Macedonian victory in a battle somewhere in Thessaly (home of Mount Olympus) thanks to the soldiers’ choice of footwear – but some scholars suggest that the name is a composite of ‘Thessaly’ and ‘victory’ (nike). Thessaloniki is the second largest Greek city and home of one of the busiest European ports:
Thessaloniki was successively a Macedonian, Roman, Byzantine, Ottoman and Greek city, and its history oozes everywhere; you turn a corner and bump into a UNESCO site or some ancient ruins. This church, Transfiguration of the Saviour, snuggled in the busiest commercial district, was built in 1345:
Only the lorries are moving in this street: the other two rows are parked vehicles. Space is scarce, so double parking is the norm. If you have stopped legally by the kerb and want to leave, tough σκατά (skatá):
Three of Greece’s largest universities are based in Thessaloniki, which hosts over 200.000 students. Lots of cheap food options is one of the perks of a student city. As a downside, Thessaloniki is covered with graffiti, some of them proving that higher education doesn’t stop you from being foolish. When Brazilian playwright Nelson Rodrigues (1912-1980) was asked what advice he would give young people, his answer was ‘grow old’:
The graffiti vandals deface monuments and historical sites with abandon, but they seem to spare religious buildings. Candle stations annexed to a church like this one are everywhere, and they are well supplied with genuine beeswax candles (Greek beekeepers must be very grateful). People of all walks of life go in, light a candle and move on:
Flags of Greece and the Greek Orthodox Church side by side at the Church of Agia Aikaterini (13th-4th c.) The Church’s power in Greek society cannot be overestimated. The whole Mount Athos peninsula is an autonomous region under the jurisdiction of the Patriarch of Constantinople, not the Greek parliament. So the monks set their own rules, such as forbidding access to women and females of other species (cats are exempt for pragmatic reasons: they control rodents that infest the monasteries). Greeks wishing to be cremated after death will have to arrange for their carcasses to be shipped to Bulgaria or other border country, because cremation is a no-no for the Orthodox Church:
This tombstone discarded in an empty lot between two busy streets is probably a relic from the Jewish Cemetery, which once covered a huge chunk of the municipal area, housing some half a million graves. Its size reflects the fact that for a long time Thessaloniki was the only city in the world with a Jewish majority, thanks to their migration to Greece after being expelled from the Iberian Peninsula in 1492. The local authorities started encroaching on the cemetery after a catastrophic fire that destroyed most of the city in 1917, but the end came in 1942 in the hands of the German invaders. Thousands of headstones were used as building material all over the city, including churches (Mark Mazower’s Salonica, City of Ghosts is a captivating historical account of the Jews and other peoples of Thessaloniki):
The White Tower, one of Thessaloniki’s most famous landmarks. Built in the late 15th century to replace a Byzantine fortification, the White Tower was once known as the ‘Blood Tower’, as it served as a prison and a place of executions. Its current name came to be in 1890, when the tower was thoroughly whitewashed by one convict in exchange for his freedom. We can achieve remarkable things when the alternative is to have our head lopped off:
St Demetrius’s ciborium (a freestanding sanctuary), which according to reliable sources – the dreams of several of Thessaloniki’s citizens – marks the spot where the saint’s bones are interred inside St Demetrius church, a UNESCO site. Demetrius was skewered by soldiers during the Christian persecution by emperor Galerius in 306 AD. The church was ransacked by the Saracens in 904 AD, and again by the Normans in 1118. Nowadays flocks of Orthodox Christians, many of them Russians, queue to get in the ciborium, kiss the symbolic tomb and light a candle. Holy relics are a big thing for the Eastern Church, but they are small fry compared to Catholics’ sacred knickknacks. In 1100 Rome, churches offered pilgrims a peek of Jesus’ blood and flesh, remnants of the loaves and fishes he delivered, the Ark of the Covenant, heads of St Paul and St Peter, and milk from the Virgin’s breasts (Matthew Kneale: Rome: a history is seven sackings):
The Rotonda from early 4th c., another UNESCO site, is a magnificent example of Roman architectural prowess. The centre of its dome is 30 m high and its walls are 6 m thick, so no earthquake managed to bring it down. Curiously, nobody is sure why it was built:
First, the view from my cabin on Tuesday: Isabela island:
And Wednesday’s “traditional Ecuadorian lunch”. It started off with a drink composed of purple Ecuadorian liqueur (at bottom) and pineapple juice. It was a good aperitif, but I don’t know what the booze was made from.
Ceviche with delicious pan de yuca: Ecuadorian (and Brazilian) cheese rolls made with cassava flour. They are addictive.
A palate-cleansing sorbet, whose identity was a mystery.
Mains: roast suckling pig (I asked for extra skin) with a cheese-and-corn vegetable and “towers” made of potato. Excellent, and quite filling
Dessert: dulce de leche cake, two cookies sandwiched around a chocolate filling, a piece of very bland cheese (like Indian paneer), and a piece of cream-filled chocolate. This lunch was so filling that I skipped dinner: I had NO appetite for the rest of the day.
Sunset on the islands:
Here’s where we were yesterday: off Santiago Island (formerly known as “James Island”). Darwin landed here—one of four islands on which he spent time.
A hearty breakfast. Some fruit juice I can’t identify, Ecuadorian latkes (o! for some sour cream!), a dish called tigrillo, made from scrambled eggs and green plantains (excellent), eggs, sausage, and fresh pineapple.
A morning Zodiac ride around the coast where we couldn’t land. You can see that the cacti are the first plant colonizers of the lava, making dirt for plants to follow. Note all the bird poop:
A Galápagos fur seal (I will call it a fur sea-lion because of its external ears). It has its bairn:
Shortly thereafter, we took a ride in a glass-bottom boat. It was my first trip in one, and it was okay, but not as good as snorkeling. (I can’t snorkel as I don’t have my prescription mask with me, and I’m blind without it.)
A mess o’ fish through the glass bottom. I have no idea what they are.
And a Santiago lava lizard. According to the Reptiles of Ecuador site, this must be Microlophus jacobi.
The front feet of a marine iguana. The wicked claws are to help it grip the rocks as it grazes on algae.
And the clawed rear feet:
This species of yellow land iguana, Conolophus subcristatus, had gone extinct on Santiago but was reintroduced. It was a big success, and is doing well. This one, we were told, was a honking big male.
A front-on view of the animal above:
Lazing in the sun:
This smaller and less yellow individual, I was told, is a female.
A piece of lava that had contained gas bubbles:
A Galápagos fur sea lion with offspring:
And a happy pinniped face:
A non-endemic yellow warbler: the only yellow bird in the islands.
A handful of sand reveals sea urchin spines, shells, pieces of lava, and miscellaneous “sand”:
And a rare sight, a pair of mockingbirds, the Galápagos birds that did make it into On the Origin of Species as exemplars of divergence after geographic isolation (nowhere in that big book will you find a mention of finches). There are four species on the archipelago; this one is the Galápagos mockingbird, Mimus parvulus.
A good shot of one. They’re hard to photograph as they’re always flitting about.
I’m a day late with this one, usually posted the day after, and we had a great day on Santa Cruz yesterday, seeing a gazillion giant tortoises and a gazillion pelicans (and a seal) importuning the vendors at the fish market. Stay tuned.
A few miscellaneous shots from yesterday. Here there’s an open-bridge policy (it’s relaxed here; we don’t even have keys to our cabin doors, so they’re always unlocked). A couple photos of the bridge:
The captain making slight adjustments to the course. Most of the time the ship is on autopilot, but adjustments are needed fairly often as the GPS isn’t perfect.
There are two wheels: the hydraulic main wheel seen above, and an old-fashioned wooden wheel that works manually and is used only in emergencies.
The radar readout of where we are. Land (the islands) are at the. bottom, and our course is the pink line.
And a view of Daphne Major, the island made famous by the work of Peter and Rosemary Grant on the finches. It’s volcanic, of course, but there is no water on it, and for their several-month stays the Grants had to lug water and supplies along a human chain up to the top from the sea. Tough work, but they accomplished a lot. (They lived in a small cave with a tarp over the front.)
We went right by Daphne Major. You can see how daunting it is: dry, nearly 400 feet up, with a tuff crater at the top.
It’s dry as hell: not a tree on the island. The Grants’ work on the finches, especially natural selection on the medium ground finch Geospiza fortis, was popularized in the Pulitzer Prize–winning book The Beak of the Finch by Jonathan Weiner although evolutionists had long followed it.
Lunch on Sunday. First, Logro de Papa soup; traditional potato soup with cheese topped with avocado.
Mains: Braised chicken breast and veg with sweet fried plantains and rice
Dessert: rice pudding with blackberry sauce. The food is very good on board, one of the reasons to travel with Lindblad
I give my first lecture today: “Why evolution remains true”, acquainting the passengers with what the modern theory of evolution consists of, why it’s both a theory and a fact (like the “germ theory” of disease), and then give them the evidence for evolution. Wish me luck!
We had a 2½-hour walk on North Seymour Island this morning. The weather was lovely: not too hot, overcast (best for pictures), and with a cooling bit of wind. And the animals were all out and on display.
First the ship, National Geographic’s Endeavour II, photographed from shore. It’s not large (26 staterooms), making for a pleasant, uncrowded existence.
The breakfast buffet, only a small part of it shown. I have to restrain myself because in Chicago I eat only one meal a day, and the food is great aboard. Yogurt, fresh fruit, pancakes, omelettes to order, all kinds of muffins and breadstuffs, fruit juice, fried eggs on crispy tortillas con queso. I must restrain myself, and have decided to have a smallish breakfast (I usually have only coffee), a large lunch, and a very small dinner. The food is excellent.
Here’s North Seymour Island, a tiny (1.9 km2 !), scrubby islet just north of Santa Cruz. It’s small, but absolutely overflowing with lizards, iguanas, birds, pinnipeds, and finches:
Animals. First, the endemic swallow-tailed gull, according to Wikipedia “the only fully nocturnal gull (and seabird) in the world.” (I may get some of these wrong, as I’m going by what the guide said, and I may have forgotten. I welcome corrections.)
An older father booby sitting atop his chick. Note the ring of feces around the nest. Can you see the chick in front?
A booby family, mother atop egg. The male and female switch incubation while they take turns getting fish in the ocean:
The blue feet of the male booby. Only the males have the coloration, and of course it’s a product of sexual selection, used in luring females. The males “tap dance” slowly while displaying their feet and also extending their wings and calling. The females are looking for. . . . well, we don’t exactly know.
Another booby with two chicks (the number varies from 1-4 or so). We thought the chicks were dead, but the guide assured us that no, they just rest like that. They were right by the trail, showing the remarkable tameness of the animals on the Galápagos—something noted by Darwin.
A closeup of one of the chicks, probably about two weeks old, we were told:
The magnificent frigatebird, a species native to the archipelago but not endemic. Again showing sexual selection, the male has an inflatable red pouch that he blows up during the breeding season, comme ça:
A frigatebird chick:
My first finch! I think the naturalist said it was a medium ground finch, made famous by the work of the Grants (see below). Sadly, it’s backlit, and you can’t get too close to these puppies:
Two views of the Galápagos land iguana, one sister species of the marine iguana (there are three species of endemic land iguana in the archipelago, but the number is disputed):
One of seven endemic species of lava lizard in the archipelago. Don’t ask me which one, but perhaps Greg will know:
A Galápagos sea lion, another endemic species; this one has a young pup. You can tell this is a sea lion rather than a seal (there’s one endemic of each) because it has external ears. (A convenient mnemonic is that “sea lion” is longer than “seal” and thus has an extra feature: the ears.)
An endemic cactus, Opuntia galapageia (there are several subspecies). It serves as food the for the land iguanas, and you can see where it’s been nommed by them. On other islands the giant tortoises eat them:
One thing that impressed me when I first came here over a decade ago was how much life there is on these barren, lava islands. It all comes from the fact that in this area the sea is rich in nutrients and fish. Look at all the signs of birds:
More signs of life, with a famous island in the background. Can you name it?
Yes, it’s Daphne Major, famous among biologists as the place where Peter and Rosemary Grant, along with their students, studied the finches and provided the paradigmatic case of natural selection: selection for beak size in the medium ground finch over a year of drought (1976-1977). This remarkably rapid instance of selection was described in a Pulitzer-Prize-winning book by Jonathan Weiner, The Beak of the Finch.
Here’s Daphne Major to the left and Daphne Minor to the right:
Finally, a rat trap on the island, designed to removed a dangerous predator. The Galápagos National Park is a kindly place, and they do not kill the rats, which are trapped with pheromones. When the traps have accumulated a few rats, they take them to mainland Ecuador and let them go (or so I’m told).
That’s a lot of stuff to see in a bit over two hours!
We had a late arrival in Guayaquil two nights ago and were ferried directly to our hotel, which was quite spiffy. Here’s my room:
After a restive night, I had a substantial Ecuadorian buffet breakfast (lovely tamales and fried plantains) and we were bussed to the Guayaquil airport for our 1 hour, 40-minute flight to Balta in the Galápagos. And here’s my nice cabin on the National Geographic Endeavour II:
And so here we are, and we’ve already taken a two-hour hike and swim on the beach (“Las Bachas” beach on Santa Cruz Island.
Here’s some wildlife we saw just a short walk; I’m not including the diving blue-footed boobies as I couldn’t get a good photo. There were also frigatebirds and a heron. These photos are severely de-pixillated because the internet is REALLY slow!
The famous marine iguana, the world’s only marine lizard and also the world’s only totally herbivorous lizard (besides its regular diet of algae, it may nom a few bugs here and there):
A non-endemic but native flamingo:
Sally Lightfoot crab:
The endemic Galápagos sea lion. This one was uber-tame and came right up to us to inspect the humans. We kept our distance (two meters by law in the islands):
Today we have a long hike on North Seymour Island, with promises of much wildlife, and in the afternoon a beach landing (with swimming) at Rabida.
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.
