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.
The weekend is nigh, but there’s no rest for ducksitters. My 25 pounds of duckling starter food should be arriving today, tomorrow I need to buy more corn and generic Cheerios, I’ve ordered three more bags of mealworms, and Anna is picking up giant bags of organic corn (only the best for our ducks!) at Costco.
Meanwhile, all is well with Anas plathyrhynchos at Botany Pond. Everyone (save Hank) got two good meals today. Here’s Hanks and Frank palling around in the pond this morning, and then doing the Synchronized Double Dabble:
Tell me that this isn’t the cutest thing you’ve seen today!:
Honey is a great mom. I’d adopt her if I could. Note that there are still eight ducklings:
Lined up for the afternoon feeding. They come instantly to my whistle:
And the usual melee:
They’re resting on the tree island now, after having their postprandial preening; and I can go home happy.
Meanwhile, the turtles have totally taken over the Duckling Plank for sunning, making it bend under their weight:
This is a good video of birds going after humans, but they are NOT evil: they’re protective! Note the preponderance of waterfowl among the attackers, including some ducks!
My favorite, Ceiling Cat help me, is when the duckling goes for the dog’s penis at 43 seconds in.
One of the striking observations about life on oceanic islands—those islands, like Hawaii and the Galapagos, that arose, bereft of life, from volcanic activity below the sea—is the prevalence of native birds, insects, and plants, and the paucity of native reptiles, mammals, and amphibians. (Continental islands, like Great Britain, that were once connected to larger land masses, don’t show this pattern.)
Darwin was the first to make this observation and show that it supported his theory of evolution. Plants, insects, and birds can more easily get to islands, where they evolve in relative isolation into new species, while mammals, reptiles, and amphibians can’t easily cross large expanses of seawater to colonize distant islands. His view could be summed up as biogeographic patterns = dispersal + evolution.
One of the ways that plants get to islands (besides via their seeds floating in seawater) is through bird movement: birds eat fruit and seeds, fly to an island, and the seeds germinate from the bird’s post-migration poop. In fact, I think a lot more plants have arrived on islands this way than by seed flotation, but don’t quote me on that.
But more than plants can get to islands in bird poop. A new short paper in Ecology by S. Kenji et al. (reference below, free pdf here) shows that stick insects (phasmids) produce hard-shelled eggs that can remain viable and hatch after they pass through a bird’s digestive tract. Moreover, since the eggs don’t require fertilization (they’re from “parthenogenesis”), they don’t have to be fertilized right before being laid, as most insect eggs are. They can simply be nommed by the birds right after being laid, or ingested by gobbling a pregnant female.
The eggs of many stick insects are sculptured like seeds and, more important, have a hard layer of calcium oxalate on the outside that is dissolved only by acidic environments like bird stomachs (this layer appears unique to phasmids). You can see some of these tough eggs in part “B” of the figure below, taken from the paper.
The authors fed eggs of three species of phasmids, mixed with an artificial diet, to Japanese brown-eared bulbuls (Hypsipetes amaurotis), which they claim is one of the main predators of stick insects. They then collected fecal pellets of from the birds when they were pooped out within three hours, and measured hatchability of the eggs. Those hatchabilities were 5%, 8.3% and 8.9% (sample sizes between 40 and 60 eggs per species).
The figure below shows bulbuls eating a phasmid, the eggs, and a nymph of one phasmid species:
(From paper): FIG. 1. (A) The parental brown-eared bulbul Hypsipetes amaurotis feeding the stick insect Ramulus irregulariterdentatus to its chicks. (B) Intact Ramulus irregulariterdentatus eggs defecated by the brown-eared bulbul Hypsipetes amaurotis. Bar = 2 mm. (C) First instar nymph of R. regulariterdentatus hatched from the egg defecated by H. amaurotis.
One obvious conclusion is that, given that bulbuls can fly about 40-60 km/hour, they could disperse phasmid eggs over a hundred kilometers (eggs are produced at about the time the Japanese brown eared bulbuls migrate). The authors fed eggs excised from adult phasmids to the birds, which suggests further that the birds could ingest a bunch of eggs at once simply by eating a pregnant female (they didn’t do this test).
The next questions are these:
1.) Did the eggs evolve that hard coat to facilitate dispersal? There are advantage to dispersing your offspring widely, especially if local predation is high or environments uncertain, and many species of animals have evolved elaborate dispersal mechanisms. (Fruits with seeds inside are one of these!). This is possible, but the authors prefer the idea that the tough eggs evolved to reduce parasitism by wasps. But of course the coat could have evolved for several “reasons” (and by that I mean there could have been more than one reproductive advantage to toughening up your eggs).
2.) Have phasmids actually dispersed this way? We don’t know, as the biogeographic studies haven’t been done. As the authors note, this should show up as evidence for wider dispersal of parthenogenetic phasmids than of their sexually-reproducing relatives:
If avian dispersal is important to stick insects, the phylogeographical patterns should reflect occasional long‐distance dispersal events (e.g., Miura et al. 2012). In addition, the patterns of spatial genetic structure will differ among stick insects with parthenogenetic reproductive capability (and hence potential avian dispersal) and non‐parthenogenetic stick insects. The phylogeographical patterns in these stick insects thus deserves further studies.
Further, stick insects themselves should in general show dispersal different from non-stick insects (I don’t mean Teflon ones!), since some of the former have the ability to get their eggs dispersed hundreds of kilometers. But all this awaits further study, as there was no reason to investigate those patterns before this new paper appeared.
“Education is not meant to make people comfortable. It is meant to make them think.”
—Hannah Gray, President, University of Chicago, 1978-1993
This 11-minute video, which lauds the University of Chicago as a bellwether for free speech on American campuses, was put out by “We the Internet TV”, which I suspect is a somewhat conservative organization (I’m just guessing based on the tone and the call for “ideological diversity,” which you don’t hear from the Left). But this video is mercifully free from right-wing politicking. There are conservatives interviewed, but also some liberals, including Geoff Stone (the law professor who helped develop our free speech code, the “Statement on Principles of Free Expression“), and Professor Ceiling Cat, who has a voice-over about 4 minutes in. On the whole, I think it’s not bad, though the narration is a bit, well, eager.
One bit that interested me was the role of the famous Robert Maynard Hutchins, who became president of the University of Chicago at age 30, serving in that role from 1929-1945, and then as Provost (the chief academic officer) from 1945-1951. He not only abolished varsity football, but shaped the undergraduate college and its famous “great books” curriculum. Hutchins was also a fierce advocate of free speech; as you’ll learn from the video (and this was new to me), during the McCarthy era he explicitly invited the head of the Communist Party of America to speak here, and then refused to bow to the State of Illinois’s demand that the Communist be disinvited.
The video gives you a taste of what it’s like to be here, and shows several deplatforming attempts. It ends with some worry about whether the University’s principle of butressing free speech will succeed in view of the faculty and students’ call for Steve Bannon’s upcoming talk to be canceled. I can pretty much assure you that it won’t be, and that the University will deal with any attempts to disrupt it.
Part of the videomakers’ notes:
Why is the University of Chicago the place that’s leading this fight? And can it resist the mounting pressure to abandon its commitment to free speech? We the Internet TV’s Rob Montz went to the Chi-town campus to find out.
A related video was made for a Chicago Tribune editorial on the U of C as “the University of Common Sense”; this one shows some pushback by students, and more discussion by Geoff Stone.
My dad was trained as an economist, and one thing he taught me when I was very young is that tariffs never benefit the country that levies them—or anyone else save perhaps a few people in “protected” industries. Yet Trump promised to engaged in trade wars, and people voted for him. Now they’ll get to see what happens.
Yes, yesterday The Donald just levied tariffs on steel and aluminum imported from three major trading partners: Canada, Mexico, and the European Union. The duties are 10% on imported aluminum and 25% on steel, and took effect at midnight last night. These three areas provide, according to the New York Times, half of the metal imported into the U.S.
Predictably, these countries are threatening to levy, and almost certainly will levy, duties on products imported from America, products like blue jeans, cigarettes, bourbon, and so on. People here will lose their jobs, prices will rise, and everyone loses except—perhaps!—some in the steel and aluminum industries.
After all these years, I still can’t see that what my dad taught me was wrong. The principle of comparative advantage, with each country producing what it produces best and cheapest, and selling those products worldwide without the impediment of duties, seems eminently reasonable from the viewpoint of both economics and employment.
Mexico, the EU, and Canada are fighting back, and rightfully criticizing this stupid move. Why on earth would any American favor it?
We have another batch of lovely arthropod photos from reader Mark Sturtevant:
We begin with two species of deer flies, which I am sure are viewed not very fondly by most readers. They can be rather beautiful, however, and it is only the females that are blood suckers. The first looks like Chrysops moechus, and the second seems to be in the Chrysops flavidus group of species. This one had sunk its proboscis deep into my thumb but I felt absolutely nothing.
During the summer the family took a vacation to San Francisco. Although it was of course too cold for a reliable abundance of insects, I could at times escape the usual tourism to explore the spectacular gardens in and around Golden Gate Park. There is a famous and ancient botanical garden just outside the park that had a butterfly house which held many native species. Two of special interest to me included the lovely buckeye butterfly (Junonia coenia), and the picture after that is of a mourning cloak butterfly (Nymphalis antiopa). I was especially glad to see the mourning cloak since that is a species I had never photographed. Although very long-lived, they prefer wooded areas and there they only spend brief periods in flight. Through most of the summer they estivate and when they do actively forage for food they prefer to feed on tree sap and not flowers.
Within the Golden Gate Park there are extensive nature trails, and in one region host plants are maintained expressly to provide a habitat for pipevine swallowtails (Battus philenor). Pipevines!! I love those butterflies, especially the males which have iridescent blue hind wings as shown here. The local subspecies in the San Francisco area had been severely threatened by development, and so there is a significant grass-root effort to cultivate their host plant to help recover the population. You have to love the San Franciscans! I saw an adult female flying around, but she would not sit for me. But there were many larvae on the pipevines in the park, and the next pictures shows one. Their coloration is a warning that they are toxic to predators. The pipevine chrysalis in the next picture was one of many on a building nearby.
Last Winter I was visited by a student who wanted to show me cellphone pictures of a spider that she had found at a nearby lake. I about fell out of my chair since what she had were pictures of a six-spotted fishing spider! This species (Dolomedes triton) is a large spider that is a close relative to our huge nursery web spider (D. tenebrosus). D. triton is slightly smaller in leg span, but is more robust in build.
Six-spotted fishing spiders are basically aquatic, and are typically found sitting on floating vegetation out on the water or lurking along the the waters’ edge. They are powerful hunters that can lunge into water to take small fish, and they will also go underwater to hide. When submerged, they are kept effectively dry by a dense pile of fine hairs that traps air around their body. I had no idea that this species was around here, and once the weather warmed up again I definitely was on the lookout for this lovely spider. I found them soon enough, as shown in the final pictures.
The first of these pictures shows one sitting out on a lily pad. When I dragged the lily pad closer to shore for pictures she quickly dove into the water. I carefully started to turn the lily pad over and she immediately popped back out, so she was probably just clinging to the underside of the lily pad. Their behavior does not seem that different from nursery web spiders in that they are strongly thigmotactic, meaning they really want to have something under their feet. It is a bit of a relief that these large and fast spiders are not inclined to jump!
The last picture is one of my favorite pictures from last summer. At a pond I found a big female fishing spider eating a dragonfly (I think it was a blue dasher dragonfly), but she was sitting on a piece of styrofoam in the pond. So I used one of the poles that I carry to drag the trash to a patch of lily pads, and then I pushed the Styrofoam under water. It was a great fortune that she immediately scrambled over to the lily pads, hauling her meal under her body like a leopard with an impala. I could then move the lily pad close to shore for pictures. For this one I was lying flat on my stomach in the very squelchy and fetid mud. After all that I was a very messy but very happy boy. If possible, I recommend trying to enlarge the picture by double-clicking on it to better appreciate the fine pile of hairs that provides an effective waterproofing system for these amazing spiders.
It’s JUNE! June 1, 2018, and the month that summer begins. It’s National Hazelnut Cake Day, a comestible which I’m sure is delicious, though I’ve never had it. Further, it’s also Neighbour’s Day, though the link gives no instructions on what to do about it. Borrow a cup of sugar?
On June 1, 1495, the monk John Cor of Fife, probably an apothecary on the side, records the first known mention of Scotch whisky. The data from Wikipedia: “To Brother John Cor, by order of the King, to make aqua vitae VIII bolls of malt.” — Exchequer Rolls 1494–95, Vol x, p. 487.
On this day in 1533, Ann Boleyn was crowned Queen of England; she lasted three years before being beheaded. On June 1, 1812, U.S. President James Madison asked Congress to declare war on the UK, beginning the War of 1812. On this day in 1916, Louis Brandeis became the first Jew appointed to the U.S. Supreme Court, serving until 1939. On June 1, 1962, Adolf Eichmann, abducted from Argentina, was hanged in Israel. And a banner day for me: it was on this day in 1967 that the Beatles’ Sgt. Pepper’s Lonely Hearts Club Band album was released—the album that made me an atheist. On this day in 1974, the Heimlich maneuver was published in the journal Emergency Medicine. You may not know that it’s not now recommended as the first course of action for conscious but choking people. Or so Wikipedia reportsm (my emphasis):
From 1985 to 2005, abdominal thrusts were the only recommended treatment for choking in the published guidelines of the American Heart Association and the American Red Cross. In 2006, both organizations drastically changed course and “downgraded” the use of the technique. For conscious victims, the new guidelines recommend first applying back slaps; if this method failed to remove the airway obstruction, rescuers were to then apply abdominal thrusts. For unconscious victims, the new guidelines recommend chest thrusts.
Finally, on this day in 2004, Terry Nichols was sentenced to 161 consecutive life terms without possibility of parole for his role in the Oklahoma City bombing—a Guinness World Record for the longest prison sentence in recorded history.
Notables born on June 1 include physicist Nicolas Léonard Sadi Carnot (1796), Brigham Young (1801), Andy Griffith and Marilyn Monroe (both 1926), ecologist Richard Levins (1930), Pat Boone (1934; he’s still with us at 84), Morgan Freeman (1937), Frederica von Stade (1945) and Heidi Klum (1973). Those who died on this day include U.S. President James Buchanan (1868), Lizzie “The Axe” Borden (1927), Hugh Walpole (1960), Paula Hitler (Adolf’s sister, 1960), Adolf Eichmann (1962; see above), Reinhold Niebuhr (1971), David Ruffin (1991) and Yves Saint Laurent (2008).
Most of you probably don’t know that Hitler had a sister, who of course kept a low profile after the war. She gave but one interview (excerpt below), and was said by her American interrogators to have had a remarkable resemblance to Adolf. Well, judge for yourself (it may help to Photoshop in a mustache and the Adolfian hairdo:
A small bit of the one interview she gave, most of which has been lost:
Meanwhile in Dobrzyn, the Hili dialogue needs a bit of explaining. Malgorzata notes, “Andrzej means that the best thing you can do with a good advice is to give it to somebody else and forget it. You can also forget it without giving it to anybody.”
Hili: The weeds under the trees are taken care of but it’s time to mow the grass.
A: I love good advice, I immediately hand it over to others.
In Polish:
Hili: Pod drzewami chwasty wypalone, ale trawę pora skosić.
Ja: Kocham dobre rady, natychmiast przekazuję je innym.
In Winnipeg, Gus ignores the lovely flowers for he sees something else—probably a squirrel, which, he’s heard, tastes like chicken.
From Matthew, who notes that we all need to learn how to pronounce “Euler”:
Per Kraus wants students to stop saying "Yuler-Lagrange" equation. This may help them remember how to say "Euler":
A very smart dude known as Euler Was blind but an unceasing toiler. That man was the guy Who said e to eye pie is .. Can't tell you. That would be a spoiler.
There once was a wombat named Plum, with a deep seated itch on his bum. But a useful stone pot, quite hit the right spot, Now Plum is no longer so glum. pic.twitter.com/Owr9nheIut
Those are some fugly sandals that Einstein bought! But of course he never cared about his appearance.
In the summer of 1939, Albert Einstein came into David Rothman's Department Store near the Long Island beach looking for "sundials." Einstein pointed to his feet. Rothman realized he meant "sandals," sold him a pair, and later posed for a photo with him: https://t.co/oFycLseCxEpic.twitter.com/ddwURLT2Md
