Monday, January 22, 2018

Birds (Parts 1 and 2)

We had two weeks of discussion about birds, so I thought I'd summarize them both in the same report. Part 1 starts with a discussion of pet birds and how to care for them, and then expands from there; Part 2 focuses on the relationship between birds and dinosaurs and discusses birding and birds of the world.

Parrots need unfiltered sunshine, ideally outdoor if it's not cold. This is why you can get "avian lightbulbs for indoor birds. Birds also need calcium, from cuttle bones or from eggshell powder. Equatorial parrots get jet lag if they don't have 12 hours of light and 12 hours of darkness.

Parrots also need a flock. They're sad by themselves, unless their owners spend quality time with them. They can develop OCD and pluck their own feathers. Some more info on parrots.

Some parrots have taken up residence in cities like San Francisco.

Birds can be territorial. They communicate through calls, body language, and biting. People often misinterpret their biting. When they are content they grind their beaks (certain parts of the beak keep growing and need to be ground down). When they fluff or preen it means they feel safe.

Cliff noted that birds are dinosaur descendants, and Kimberly mentioned how scientists had turned off a beak gene in a chicken and it had developed a dinosaur-like snout with tiny teeth. Brian said you can weight chickens so they walk like a Tyrannosaurus Rex.

Corvids (crows and ravens) are what dinosaur evolved intelligence would be like. They can plan for the future.

Birds express themselves differently from mammals because they don't sue facial expressions. The porgs of Star Wars are mammalized puffins... basically puffins, because they couldn't be shooed off the island, with their faces altered so they would have facial expressions. If you wanted to have interesting aliens in a secondary world, you could give them avian communication strategies.

One needs to keep pet birds intellectually engaged. They can get bored easily. Their sexual behaviors can be a problem because they can cause aggression.

Kat asked about birds in space. It could be a problem for birds to grasp with their feet and sleep if gravity could not help them keep hold. They apparently also need gravity to swallow.

Parrots use their feet as hands and their beak like a thumb. They are good climbers because two of their toes point forward and two backward.

Emus shed feathers when they are stressed, as in a fight or flight scenario. Kat told us that hand-feeding emus is terrifying.

Good and bad luck are often associated with birds. There are many mythical birds across cultures, like the Roc and the Phoenix and the Firebird.

Birds can imitate human language, and the lyrebird can imitate almost any sound. I report on Birds: Part 2 below the video.

Part 2:
We started out this session by having Brian tell us about birding. You basically go out and look at birds. Many people get very serious about collecting and cataloguing sightings over the course of their lives, and can have seen thousands.

A new piece of DNA research has determined that falcons aren't classed with hawks and raptors any more, but are closer to parrots.

Humans love categorizing things, so we created the idea of species. Species is something of an artificial category, though. Usually people have said two different species can't produce viable offspring, but this isn't true. There's such a thing as a "ring species." A group of arctic gulls can reproduce with those to the west of them, but not with those to the east, in a ring all the way around the pole.

Darwin studied the speciation of finches in the Galapagos islands.

Dinosaurs are birds. When I was a kid, archaeopteryx was considered the single "bird dinosaur," but now a great many (if not most) of them are considered to have ben feathered.

In the old model of animal classes, there were amphibians, reptiles, birds, and mammals. In the new model, reptiles break into snake/lizard, bird, and turtle/crocodile groups.

The more we learn, the more we have to re-classify and change things.

In the 1880s, there were "dinosaur wars" where dinosaur hunters in Utah tried to sabotage each other.

The idea of "cold-blooded" vs. "warm-blooded" has been broken down at this point. There are many ways in which organisms can regulate their body temperature. Feathers were an early adaptation to control body temperature. But since they also assisted with things like jumping out of trees, it became possible for them to adapt into flight feathers.

Roadrunners jump down onto their prey.

Most of the feathers on any given bird are not flight feathers, but are for heat insulation.

Even though many birds fly, they will avoid flying if they can, because it's so energy-intensive. If birds end up on an island with no predators, they will stop flying.

Other things also fly - and we decided to talk about them the following week. This group includes bats, insects, and three-foot dragonflies. In a high-oxygen environment, insects can grow to be very large.

I recommended the David Attenborough series of videos The Life of Birds (it's amazing).

Cliff recommended the book "After Man" by MacDougal and Dixon, and the related video series "The Future is Wild." One of its ideas was that penguins would fill niches that had earlier been filled by other types of animals.

Penguins carry their knees internally. They can take over huts and live in them. Penguin movement is a lot like flying, but their medium is not air. They can play in bow waves like dolphins.

Rheas, cassowaries, ostriches, and emus are among the large flightless birds of the world. Emus once won a land war with armed humans in Australia.

We asked, given that flight and large brains are both energy intensive, how it would be plausible to create an intelligent/sapient avian species. Kate said they would have to have a really abundant food source that they can't easily run out of. Intelligence is relatively common in omnivores...and some birds are omnivores. Often, we don't really know everything a bird eats. Even hummingbirds eat 25% insects. Birds' habit of scattering seeds is good for the propagation of trees, so they could easily be imagined as agrarian.

Even though we think of birds as oviparous, some of them have pouches and carry their babies while flying, and others carry their babies on their backs, particularly the aquatic birds who must protect their babies from becoming too wet when their feathers are still downy.

Ostriches have lots of babies, as many as 20 chicks at a time, but many of them die and some of them make it. Other birds do more to care for their babies. Quail will have community guarding and lookout birds to protect their nests on the ground.

Measuring the length of bills is hard because it's hard to tell where the bill ends and the skull begins. Bills were often measured from tip to nostrils, which made Kiwi birds the bird with the shortest bill, because their nostrils are at the tip of the bill. They have quite an advanced sense of smell.

Tomorrow, we'll be joined by author Ann Leckie who will be talking about her Imperial Radch novels with us at 4pm Pacific. I hope you can make it!