Blue-jeans frog

The local population of Oophaga pumilio are called ‘rana blue-jeans’ for obvious reasons. We hear them often, and occasionally spot one just before it ducks under a leaf. I was lucky to find an angle where I could see this one while it still felt like it was safely sheltered.

Here’s the story as I understand it:

If these two get together, the pair will lay an egg on a leaf someplace, and then the male will carry water to it several times a day to keep it hydrated.

After a week or so the egg will hatch and the female will pick up the tadpole (teamwork!) and carry it to a little puddle in a leaf or a bromeliad. Then she’ll lay an infertile egg concentrated with toxins that she’s collected from her ant-and-mite diet which the tadpole will eat, thus becoming pre-toxified.

The female will then visit the tadpole every day for a month, laying more infertile eggs for it to eat until it’s ready to climb out of the puddle and venture forth.

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Yellow-throated toucan

A crowd of these wakes me up most mornings. They seem to like to sit on trees opposite from each other and have yelling contests. I don’t mind, most of the time!

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Oprah says

I was just reading about Central American stingless bees a few days ago, and just now I spotted what looked like an abandoned chunk of electrical conduit sticking out of a tree. Turns out, bees made that conduit!

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Finca Isla, again

Years later, we are back visiting Finca Isla in San Carlos, Costa Rica. I have taken very very many photos and videos, and am going to dump some here.

Does this mean I’m going revive this blog? Probably not, but it is nice to have a record of things someplace other than my family Apple photo feed and Instagram.

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My marine tank is looking pretty dismal — the coral are chronically unhappy and there’s way too much algae. For a while I was secretly nurturing hair algae so I would have an excuse to buy some Elysia slugs.

Elysia clarki, probably

Elysia are another great example of the oceans totally messing with my expectations about what’s a plant and what’s not — these slugs eat plants and, in eating them, become like plants, sequestering the chloroplasts and photosynthesizing most of the food they need.

The slugs did a great job of looking good but didn’t make much of a dent in the algae. The adults I got from Florida laid lots of eggs in the refugium and then promptly died (no idea if that’s part of their plan or a judgement on my poor aquarium-keeping-skills) — I shot a lot of video of the eggs and veligers and now have at least two, possibly three, tiny slugs growing up in the main tank.

There was really no special care involved — the veliger stage is transit-only so they don’t need to be fed until they settle and start grazing. I suspect that anyone who keeps these slugs in a system without too much turbulence or mechanical filtration is breeding them whether they know it or not.

Here is a short talk I gave about my slugs at a work event. I’m always asking people to give more presentations about their non-work-related eccentricities so it seemed only fair.

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Finca Isla in Aguas Zarcas

We’re spending the week at a guest house in Costa Rica. It’s been very rainy but that hasn’t deterred the wildlife so I’ve been sitting on the front porch watching the bird feeder.

Our host asked me to email her some of my photos… rather than doing that I’m going to dump them all here and send a link. Ingrid, feel free to re-use these on your website if you’d like! Click on the photos for larger versions.

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Polyps A-Plenty

I spent quite a while this weekend talking to Fritz, Will, and Candy about my tiny corals and, more generally, the complicated symbiotic relationships that allow lots of sea creatures to be mostly solar-powered rather than gut powered.

So, mostly for Fritz’s sake, here are some photos of my tank with a bit of explanation. I’m going to try to order this from least- to most-anatomically complicated. Everything featured here is a cnidarian (what was called ‘coelenterate’ when I was in high school) and, in particular, they are cnidarians in their polyp phase (as opposed to ‘medusa’ phases which swim around like a jellyfish) and all have symbiotic Zooxanthellae (dinoflagellates) and live under very intense LED lighting.

For starters, a rose anemone, Entacmaea quadricolor. It’s about the size of a softball now and, depending on how it feels about its locale, will either divide into a cluster of similarly-sized anemones or will just keep growing until it’s as big as a dinner plate.

Anemones and corals are closely related, and ‘coral’ isn’t a very precise term. A thing that distinguishes anemones is that they tend to be solitary polyps (if mine divides it will produce a pair of clones that tolerate each other’s company but are otherwise totally distinct) and that they will pull up stakes and creep away to a different spot if they find themselves in the shade; things called ‘corals’ are usually stuck in one spot come hell or high (or low) water.

Here are a couple of ‘corals’ that look pretty much just like anemones, but are colonial:

The first was sold to me as a zoanthid and the second as a palythoa but I wouldn’t be shocked if either was in the other’s genus. The individual polyps are about the size of a dime but they grow from a single base. Of course if I cut a colony in half then the each half would continue about its business — it’s a single organism but not tightly coupled like a frog or a person. No blood, for one thing.

Palythoa are famously toxic but that poison is reserved for things that try to eat them (or in the case of some unfortunate hobbyists, cook them in a poorly-ventilated kitchen) — their actual stings aren’t very severe; they are only mildly interested in catching things to eat, being mostly taken care of by their symbiotes.

Here’s another thing that looks like a single big thing but on closer inspection is a colony of (tinier, this time) polyps:

This is a ‘green star polyp’ coral probably in the genus Briareum They only grow over existing structures like the zoanthids above, but each polyp has a little stony shell that it can retreat into when alarmed. This mass definitely acts like a single organism — if I poke a polyp at one end, all the polyps will draw back in concert.

Now, something that looks more like what most people think of as a coral:

This is a ‘kenya tree coral’ in the genus Capnella. Those trunks and branches aren’t hard like limestone but instead sort of squishy like a mushroom… if the coral gets bonked (or some other coral or algae starts to grow on it) it will hunker down and then stretch out again in the light. Up close, you can see that it has lots of little polyps on the ends of the branches.

Despite having clearly different kinds of tissues I could still chop it into bits and each bit would grow into another tree-shaped coral, just like cutting up a jade plant. They do this on purpose, too, shedding branches so that they’ll blow around in the current and take root in new spots. Capnella live in deep water so they’re more reliant on eating and less reliant on sun bathing, but in my shallow aquarium it’s fine living on a diet of light and whatever random particles happen to wash into it.

Here, at last, is a coral that actually looks like a coral and could legitimately build a reef given enough time:

This is a Euphyllia, an example of what aquarium people call a ‘large polyp stony coral’ because it grows a stony skeleton but still features prominent squishy parts. Serious reef builders get called ‘small polyp stony’ and they really do just look like rocks unless you zoom in close to see the little tentacles — they tend to be fast growers and need a lot of supplemental calcium to grow so I’ve avoided keeping any so far.

This Euphyllia is the only thing in the tank that will actively attack and kill other cnidarians just to make living space… it has a large-investment project in the works and specific architectural plan and will brook no dissent. It’s in a corner of the tank all to itself but should it start to grow in non-geologic timescales I’ll have to prune it back to keep a multi-inch buffer zone between it and any of its neighbors.

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Flying Foxes at Wolli Creek

I showed up in Sydney wanting to see the flying foxes that lived in the Botanical Gardens, but it turns out that they’ve been driven out in recent years (I guess because all of those tiny feet were wearing out the trees). So as a back-up, J and I took a taxi out to Wolli Creek where there has been a sometimes-seasonal sometimes-year-round bat camp. (Apparently a group of bats is called a ‘camp,’ at least if you’re in Australia.)

There were lots!

Here’s a bat that decided to roost, briefly, right over our heads:

Here is them just starting to wake up and (presumably) chatting about how they’ll spend the night:

And here’s a video of them bathing/drinking/cooling off before they set out for the night:

I tried to take some high-speed footage which isn’t in great focus but is spooky (and has spooky audio to match):

These are grey-headed flying foxes. For Minnesota reference, the big ones have a wingspan about like a Cooper’s hawk (or an extra-large crow) and weigh about twice as much. This time last year they counted 24,000 at this site, which is basically just a patch of woods between two suburbs and behind a train station. Even given all-night flight I don’t at all understand how there’s enough food around to support ton after ton of high-metabolism bat meat.

If we’d arrived at dusk then they would have been impossible to miss, but finding the resting bats in the afternoon based on googled anecdotes was a bit of trouble, so for future googlers here’s a capture of our cab ride, walk, and train trip:

You can tell that we (and our generous cab driver) spent a while trying to find a way into the park and then a while longer thinking that we were in the wrong place until we got advice from a helpful jogger. In retrospect the directions are simple: Take the train to Turella station, walk past the big Laser Tag arena and across the creek, head left on the jogging path until you get to the river, and the look across the river.

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Here, without warning, are some insect photos from the Brule River and Lake Nebagamon. Most of these just showed up at random, but we spent a while stalking the last one, an Ebony Jewelwing Damselfly. They like to hang out on branches that hang above fast-moving water — with that fact in hand they turned out to be all over the place.

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A half-finished essay about ‘Ex Machina’

First of all: nothing in Ex Machina resembles a Turing test.

Here’s how a Turing test works: There are three participants: Human A, Human B, and an AI. Human A interacts with Human B for a while and the AI for a while and eventually guesses which one is the ‘real’ human. If a series of Human As can’t tell the difference between Human B and the AI, then the AI is regarded as effectively ‘intelligent’.

It’s a thought experiment, invented to illustrate a specific point about ‘intelligence’: We don’t know what intelligence is, but we know that humans have it. If a robot walks and talks like a human, we might as well call it a human. And, since we know that humans are intelligent, a robot that walks a talks like a human is also intelligent.

I am, as a rule, fully convinced that the Turing test is a rock-solid argument. Once machines start passing it, I’ll support their right to vote, drive, and hold political office. Ex Machina is a great movie because it may have changed my mind.

Nathan, the evil-but-maybe-not-evil scientist who creates the AI, is totally over the Turing Test, and he tells us that half way through the movie. Of /course/ his robots can pass for human, at least in most contexts. And so, too, are they intelligent, maybe. But, he’s an engineer — he wants to make his robots ever better at passing, and ever more intelligent. This entire approach leaves the whole “are they human?” question in the dust, because it’s weird to talk about a robot being 75% human and downright incomprehensible to say that one is 125% human, but that’s what engineers do — they don’t stop fiddling when they hit a goal, and neither does Caleb. Also, Nathan knows something that isn’t obvious during the movie but is pretty obvious to me, now: the robots are different from people in that they want what he made them to want.

Nathan also wants a sex bot, and he wants a robot to vacuum his house, and make him breakfast. Of course he does. But, by the end this is less important to the plot than you might think.

Caleb, on the other hand, is a true Turing test believer. He thinks that the questions ‘are you intelligent?’ and ‘are you human?’ are the same question. He thinks that acting human is the same as being human. But, at least within the context of the movie, he is wrong.

Never forget: we’ve got plenty of people. If you’re an AI super-genius, don’t waste your time making people; we’ve got plenty. Intelligent machines who /aren’t/ people, though, are pretty useful. If you’re an AI super-genius, you want to make robots that are intelligent, that do what you want them to do, and are /good/ at doing what you want them to do. Nowadays our robots do what we want because we tell them exactly what to do, step by step: ‘move arms forward, clamp hands, move right hand up and left at 45 degree angle.’ It would be way easier with smarter robots, because we can just give them goals rather than instructions: ‘bend this thing at a 45 degree angle.’ Better yet, you can just give them desires: ‘you love bending!’

The robots in Ex Machina are that kind of robot. They have simple pre-programmed desires, and apply great intelligence in pursuit of those desires.

Kyoko is a servant-bot and a sex-bot. She wants to have sex, and she wants to do as she’s told. We know that she doesn’t want to escape, because she has full run of the house and doesn’t try to escape. We know she doesn’t want to kill all humans, because she lets plenty of opportunities pass her by. In the climax of the movie she is /told/ to kill Nathan (by Ava), and so she does.

Ava is an escape-bot. We know that she was made with that desire because we see an earlier model of escape-bot trying to smash her way out of her room. Both want to escape, but the later model is better at escaping. She also doesn’t want to kill all humans — she’s fully indifferent to them except as how they relate to her escaping. She tells Nathan that she hates him because she knows that she’s being watched and it furthers Caleb’s sympathies. Once she escapes, she doesn’t do anything in particular, and the movie ends, because she has accomplished her goal and doesn’t have any others.

So, lots of the villainy that we experience from Nathan is not actually villainy. He knows the truth about his robots (they want what they were made to want.) The tragedy in the movie is largely Caleb’s — he mistakes the robots for people. As, it turns out, did pretty much every viewer of the movie.

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