How do paleontologists find fossils? Better yet, how do they find small bits such as tiny dinosaur teeth?
In Wyoming they get help from ants.
In the video below Australian paleontologist Mikael Siversson (“Birds are dinosaurs”) describes a trip he and a colleague made to Wyoming dinosaur country in the late 1990s. The video starts with a picture of the Badlands as he begins to tell the story. Watch for four minutes — or longer if you want to learn about dinosaur teeth. It involves bathtubs.
(photo from Wikimedia Commons, screenshot from video; click on the captions to see the originals)
p.s. The toothy mouth pictured at top is the reconstructed skull of a Tyrannosaurus rex, a theropod ancestor of birds. Did birds have teeth? You bet!
In late August reports started trickling in that high numbers of migratory birds were being found dead in New Mexico. The first report was at White Sands Missile Range on 20 August but as time passed the reports became more frequent, the locations increased, and so did the death toll. By now experts believe that hundreds of thousands of birds have died — perhaps millions — not only in New Mexico (red on map below) but in Colorado, Arizona and western Texas (orange highlight on map).
Austin Fisher took a video of the carnage last Sunday, 13 September 2020 in Velarde, New Mexico.
Science Alert reports that only migratory birds are affected, not the local residents. Most of the dead birds are warblers, swallows and flycatchers and “the affected travelers seem to act strangely before their deaths, spending more time on the ground than perched in trees, and generally appearing dazed, sleepy, and lethargic.”
Unfortunately birds’ respiratory systems are so different from ours and so efficient that they succumb quickly to bad air.
We turn oxygen into CO2 in one breath — in/out. Every exhalation releases the CO2/remains of the air we just breathed in.
When birds breathe, the air that enters their bodies stays inside for two breaths — in/out + in/out. During its 4-step journey, the air molecule travels through the lungs, two sets of air sacs and into the birds’ hollow bones where it waits for the next step. Click on the diagram below to watch the airflow inside a bird.
Many birds look ragged right now because they’re molting. July and August are the perfect time to replace worn feathers because the breeding season is over, food is plentiful and they aren’t traveling on migration. The cardinal below looks moth-eaten because he’s molting his body feathers.
What a red bird eats while he’s molting affects his feathers. Red feathers get their color from carotenoids in food so a diet rich in carotenoids makes a cardinal brighter for the coming year.
Bush honeysuckle, though invasive, is a good source of carotenoids. Unfortunately it’s not as nutritious as our native berries.
This bright red cardinal is eating American beautyberry (Callicarpa americana). The redder he is, the better the ladies like him.
This dull colored cardinal must have missed the red berries last summer.
House finches have a more obvious response to nutrition while molting. Finches without enough carotenoids produce orange feathers instead of red. In Marcy Cunkelman’s photo below there’s an orange house finch on the right, a red one on the left.
You are what you eat.
(photos by Bob Kroeger, Marcy Cunkleman, Kate St. John and from Wikimedia Commons)
Like the common cuckoo and brown-headed cowbird, the striped cuckoo (Tapera naevia) of Central and South America is an obligate brood parasite. Called “saci” in Brazil or “sinfín” for its voice, this bird is more often heard than seen and that’s a shame because his behavior is so fascinating. When approaching an unknown saci, here’s what he does:
The curious dance of the saci, also known as the striped cuckoo.
All birds have them. They’re actually the bird’s thumbs. The complete structure with three to five short feathers is called the alula and is used to prevent a stall during slow flight. Pitt peregrine Dorothy demonstrates them while soaring in this 2008 photo.
The saci has black alulas that contrast with his white breast feathers so they stand out when he dances.
Mighty impressive. Show me your hands!
p.s. The striped cuckoo is called the saci in Brazil because it is related the saci of Brazilian folklore. Read more here.
(photos from Wikimedia Commons and by Jack Rowley)
On Saturday 6 June 2020, photographer Steve Gosser found a bird in the Pittsburgh area that doesn’t match any field guide. He looks like a cross between a rose-breasted grosbeak and a scarlet tanager. He sings like a scarlet tanager.
So I found this bird today that has all the expert birders scratching their heads. It appears to be a cross between a Rose-breasted Grosbeak and a Scarlet Tanager, possibly a hybrid! No one seems to have any records of a hybrid between these birds! I along with two expert ornithologists will try and relocate this bird in the morning and they are interested enough to possibly try and catch this bird and collect a blood sample so it can be DNA tested. It sang exactly like a Tanager, has black wings like a Tanager, a thinner bill like a Tanager, a red throat like a Tanager but the rest looks very much like a RB Grosbeak. I’ll keep everyone posted as to what we find out!
Here’s who the mystery bird resembles: a male scarlet tanager on the left, a male rose-breasted grosbeak on the right.
Yesterday ornithologists Bob Mulvihill and Steve Latta netted the bird and took blood samples for DNA testing. Bob says the bird “bit hard but not as nimbly as a rose-breasted grosbeak.” Rose-breasted grosbeaks have very strong bills.
Unlike a rose-breasted grosbeak, this bird has almost no red color in his axillaries (armpits).
After the blood sample, Steve had the honor of releasing the bird.
One of my favorite YouTube stars is Petra the African grey parrot who is so smart that she carries on conversations. Here she asks Google a question.
African greys are the smartest birds but they’re not the only parrots that can mimic humans voices. How do parrots speak like humans when they don’t have the same equipment we have, such as lips and teeth, to form words? The video below shows how.
p.s. I’m sure you noticed that the parrot-speaking video ended abruptly when a woman began to talk. She’s going to promote the WIX website tool but it looks as if she’s going to talk about parrots. She doesn’t. It’s very confusing! So here’s her promo and her link to WIX.
(screenshot from Petra Grey video. To watch the videos on YouTube, click on the word YouTube at bottom right after the video begins)
Flamingos’ beaks are quite unusual. Their lower mandibles are larger and stronger than their upper ones and their smiles are upside down.
Their lower jaws are fixed to their heads and their upper jaws move freely. When they open their mouths the top beak moves up like an opening clam shell. This is opposite to us humans. We drop our jaws to open our mouths and take in food.
However, flamingos eat with their heads upside down. In this position they drop their (upper) jaws to open their mouths just like we do. When they’re feeding their smiles are right side up.
Their beaks are designed to catch what they eat. From small crustaceans, mollusks and insects to tiny single-celled plants, their food is suspended in water which they capture by filter feeding, a technique they share with baleen whales and oysters.
Flamingos take water into their mouths and strain it out through the filtering mechanisms in and on the edges their beaks (see illustrations above). When flamingos are feeding rapidly they pump their tongues to suck water in and squish it out. This video from the Galapagos shows how they do it.
Gouldian finches (Erythrura gouldiae) are colorful Australian seed-eating birds that nest in tree holes in the wild or in nest boxes when bred in captivity. Their nests are always dark inside so the nestlings have unusual mouth markings to attract their parents’ attention. Each nestling has:
Four opalescent tubercles at the corners of the gape that reflect a bluish light.
Patterns inside the mouth that guide toward the gullet.
To further attract attention, the nestlings hold up their mouths and rotate their heads as shown in this video of 3-day-old chicks.
The nestlings’ elaborate show may have evolved because …
Gouldians are among the most difficult finches to breed successfully because they are not wonderful parents and have a tendency to abandon both eggs and babies, or even refuse to nest at all. People who raise Gouldians usually keep society finches as well to serve as foster parents for eggs and babies. Societies are marvelous parents and will be happy to foster other species.
Both studies correlated the annual mean summer temperature of the species’ breeding range and reached the same conclusion: As the climate heats up, birds are getting smaller.
We should expect this.
There’s a biological rule of thumb called Bergmann’s Rule which states that, within a species, populations living in colder climates have larger body size than those in warmer climates. Bergmann’s explanation is that large animals have a lower surface-area-to-volume ratio so they lose heat more slowly in cold climates while small animals have a higher surface-to-volume ratio and can cool off faster when it’s hot.
Song sparrows (Melospiza melodia) provide a good example of Bergmann’s rule because they range across North America from Alaska to Newfoundland and south to Mexico. I saw their variability up close in the Carnegie Museum of Natural History’s Section of Birds in December 2016. My photo below shows sparrows collected in Alaska in the top row, sparrows from Pennsylvania on the bottom.
Here’s a closeup placed side by side (below):
On the left, two song sparrows collected in Pennsylvania: Pittsburgh (leftmost) and Geneva Marsh.
On the right, song sparrows collected in Alaska’s Aleutian Islands at Unalaska (leftmost) and Sanak.
Alaskan song sparrows are so large that they have to be placed sideways in the tray!
Smaller size is normal where it’s warmer.
It isn’t bad news for birds and it tells us two additional things:
Birds’ bodies have been registering climate change long before we humans noticed or admitted it.