22 May 2023

Where did butterflies come from?

The question first intrigued Akito Kawahara when he was eight years old and became his lifelong pursuit. This month he and his team published the answer in Nature: A global phylogeny of butterflies reveals their evolutionary history, ancestral hosts and biogeographic origins.

Butterflies first evolved from moths when they began feeding on the nectar of new species of flowering plants usually available during the day. That shift allowed these insects to shed their earth tones in favor of the riot of colors they’re known for today, which often act to attract mates or warn predators that they’re poisonous.

— WESA-FM: Butterflies originated in North America after splitting from moths, new study suggests

The butterfly-moth connection makes sense but the place where it happened is a surprise. Scientists used to think butterflies originated in Asia, but Kawahara’s study shows they evolved 100 million years ago in western North America or Central America and then dispersed throughout the world.

The maps below show their dispersal and species counts over time (darkest colors are the highest number). Starting 100 million years ago in the Americas, butterflies first jumped to Australia and from there to Asia, Africa, and finally Europe.

Today the greatest biodiversity of butterflies is in Central and South America where this blue morpho is found.

Listen to the audio article or read more about the study at WESA-FM: Butterflies originated in North America after splitting from moths, new study suggests.

BONUS: So how do you tell a moth from a butterfly? Check out the answer here:

(photos by Marcy Cunkelman and from Wikimedia Commons, map from Nature: A global phylogeny of butterflies reveals their evolutionary history, ancestral hosts and biogeographic origins)

2 May 2023

On a hike at Hays Woods last week with Jared Belsky of the Pittsburgh Parks Conservancy we saw odd holes on a bare spot of ground, each one surrounded by a dust cone shaped like a tiny volcano. I could tell they where probably made by insects but which ones?

Jared told me these holes were constructed in March by cellophane bees.

Cellophane bees (Colletes inaequalis) are the first bees of spring, sometimes emerging while there’s still snow on the ground. They are members of the group called “plasterer bees” (Colletes sp.) described by Wikipedia below:

The genus Colletes (plasterer bees) is a large group of ground-nesting bees of the family Colletidae that occur primarily in the Northern Hemisphere. They tend to be solitary, but sometimes nest close together in aggregations. Species in the genus build cells in underground nests that are lined with a cellophane-like plastic secretion, a true polyester, earning them the nickname polyester bees.

— Wikipedia account: Colletes

Now that it’s May it’s too late to see cellophane bees making holes, but it’s not too late to learn about them and be ready to watch them next March.

p.s. Cellophane was invented in 1912 and polyester in 1928 so these common names of plasterer bees are only a century old.

(bee photo from Wikimedia Commons, holes photo by Kate St. John, embedded video by Nick Dorian on YouTube on YouTube)

27 March 2023

The worst part of Lyme disease season has just begun so let’s learn how to avoid it.

From spring through early summer the tiny nymphs of black-legged ticks (Ixodes scapularis) quest for blood meals from animals and humans. Only the size of poppy seeds, the nymphs are really hard to see. If an infected tick bites you, it will give you Lyme disease bacteria.

To prevent the debilitating disease, don’t let ticks get on your skin.

1. Choose outdoor clothing that prevents ticks from reaching your skin:
   • Light colored clothes: So you can see ticks easily.
   • Long pants.
   • Long sleeved shirt with collar + tuck in your shirt: Collar traps ticks before they walk up your neck.
   • Socks: When you bushwhack or garden, tuck pant bottoms into socks.
2. Once a year (i.e. now!) Spray your outdoor clothing with Permethrin. I know from personal experience and the experts agree that Permethrin works much better than DEET. Spray protection lasts 4-6 washings. Pre-treated clothes can last 70 washings. READ AND FOLLOW LABEL DIRECTIONS.
3. Avoid brushing against vegetation. Avoid bushwhacking. Bush honeysuckle and Japanese barberry are tick magnets.
4. If vegetation brushes you, field check your clothing for ticks when you reach a clearing. The sooner you get ticks off your clothes the better.
5. Do a daily tick check.  Yes, daily!  You might have missed one yesterday that’s still on you. Check these spots.

If you find a tick remove it correctly (here’s how) and save it for testing.  Send it here and they’ll tell you if it carries Lyme disease.

Black-legged ticks are active year round when the temperature is above freezing. If you wear protective clothing — yes, even in hot summer — you’ll save yourself a world of trouble. See more tips here.

p.s. There are lots of ways to outsmart ticks. Did you know zip pants trap ticks under the zip placket?

p.s. Be careful with Permethrin. READ AND FOLLOW LABEL DIRECTIONS. To avoid fumes and protect kids and pets, spray your clothes outdoors on a windless day and wear rubber gloves. Keep Permethrin away from the cat (see label).

p.p.s. As Mary Jo Berman points out in the comments, I should have added this last tip on how to kill ticks on your clothing. After you come indoors, put your outdoor clothes in the dryer on high for 10 minutes BEFORE you wash them. Really. It kills ticks.

(photos by Kate St. John.  tick chart from the Center for Disease Control via Wikimedia Commons.  Click on the chart to see the original)

16 March 2023

While Pittsburgh experienced a “Too Early Spring” for plants, 7 Feb to 7 March, it was also a weird time for honeybees. Thirteen days of temperatures above 54ºF(*) with blooming trees and flowers prompted honeybees to begin foraging. I often found them at the cherry blossoms but couldn’t catch one in a photograph.

This week the average temperature stayed near freezing for four days in a row so I was surprised to see a few bees emerging from the hive pictured at top when it was only 45ºF. In fact I was surprised to see the hive at all on the roof of The Porch restaurant at Schenley Plaza. It’s probably warmer up there.

Crazy spring weather, hot then sudden cold, can sap honeybee strength and make them susceptible to disease. To make matters worse freezing weather kills the flowers (food supply) so beekeepers provide supplemental feeding to help their bees over the rough spots.

Now there’s happy news about a bee vaccine, provided through supplemental feeding, that can innoculate honeybees from one of the worst diseases: American foulbrood (AFB).

Foulbrood is caused by a spore-forming bacteria, Paenibacillus larvae, that kills honeybee larvae without harming the adults. As the larvae die off, AFB weakens the colony and can quickly lead to its death in only three weeks. The bacteria is so hard to eradicate that infected hives must be burned.

Developed by biotech company Dalan Animal Health,

The vaccine, which contains a dead cell of the virus, is administered to the bees through the queen feed that worker bees consume. The worker bees then transfer the vaccine into the royal jelly and feed it to the queen. As a result, the vaccine gets deposited into her ovaries, giving larvae immunity when they hatch.

— CBS News: USDA approves vaccine for honeybees

Read more about the foulbrood vaccine here at CBS News and the press release on Business Wire.

(photos by Kate St. John)

p.s.(*) I say 54ºF because, according to the University of Maine Extension, “The minimum temperature for honeybee flight is 54º F.  The optimum temperature for flight activity is 72-77º F.”