Blogging – Page 5 – Walking Contradiction

Day 38: Comes With the Territory

I was very excited when I discovered the huge crop of Eastern Black Swallowtail eggs a few weeks ago, but at the same time I also knew that that would mean having to deal with several caterpillars that wouldn’t make it all the way to adulthood. There can be many reasons caterpillars die: poison/insecticides, virus/bacterial infection, or just a genetic fault.

I took the photo above after changing the food supply and water for one of the enclosures. Those critters strip the rue and parsley pretty quickly, and many of their droppings end up in the glass. I also change the paper towels at the base of the enclosure, as it is also littered with caterpillar poop and pieces of the plants. I count at least 13 caterpillars in that shot; there are probably a few more hidden on the other side.

But when I clean out the enclosure, I often find several caterpillars on the floor of it, unresponsive. I remove them to a separate container, in case they are infected. A couple of days ago, I gathered 6 such sad critters from the two enclosures.

I puts bits of food in front of them to see if they start munching, a sign that they are still healthy. In the photo above, both #1 and #4 eventually “woke up” and began eating, so I returned them to the enclosure with their siblings.

#2 didn’t look very good at all. In the 15 minutes between when I placed them on the paper towel and when I took the photo, it had oozed a blackish liquid. It did twitch for a little while, but was soon dead.

#3 just looked deformed. I don’t know if it had some disease or a genetic fault, but it didn’t last long after this.

I had some hope for #5 and #6, as they are in the “J” shape that that swallowtail caterpillars form themselves before shedding their skin to become a pupa. They were smaller than pre-pupas typically are, but these little guys have surprised me before. I’ve had a few that laid on the bottom of the enclosure like this, and after a couple of days I’d look in on them and they had become chrysalises! They eventually emerged as perfectly normal adult butterflies, so I was hoping that that would be the case for these two. They were both wriggling from time to time, similar to the motion they make when getting ready to molt into a chrysalis.

Unfortunately, it was not to be. #5 turned dark and stopped moving in a few hours. #6 remained twitchy for 2 days before finally dying.

It’s always hard to see these tiny creatures hatch from eggs, and slowly grow bigger and bigger, only to die suddenly for no apparent reason. But it’s part of nature, and it helps to keep in mind that by keeping them away from predators and keeping them well-stocked with food, a much greater percentage do make it maturity. All you can do is your best to help them along.

Day 37: The Limits of Dentistry

I don’t much feel like writing at the moment, as I’ve just returned from the dentist, and had a new hole drilled into my upper jaw in preparation for getting an implant to replace a tooth. The numbing agents are wearing off, and my face is starting to throb.

I don’t keep records, but back in college I had several cavities, and being broke, went to the cheapest dentist I could find (cue the rant about American health insurance). Fast-forward to my 30s, and my new dentist told me that all of those fillings were failing, and some had new decay under them. They needed to be replaced, but one in particular would require removing so much material that a new filling wouldn’t be feasible; I would need to get a gold crown. They were really expensive, as insurance only pays a tiny fraction of what they cost (cue another rant). But, they said, gold crowns are permanent! So I got the crown.

Move on to my 50s. When reviewing my x-rays, the dentist said that there was new decay under the crown. “How was that possible?”, I asked, “I thought that crowns were permanent”. Turns out that “permanent” is a relative term, meaning “about 20 years”.

The decay had spread into the tooth’s roots, so I had to also get a root canal before they could replace the crown. Now that should be that!

Jump ahead to a couple of years ago, and my x-rays showed some smoky area in the jawbone where the tooth was located. An infection! Once again, my question was “How was this possible?”. Apparently the root canal didn’t get every single bit of bacteria, and they had now spread into the bone. The only way to treat it was to extract the tooth, surgically remove the infection, let the bone regrow, and then drill into it for the base of an implant to replace the extracted tooth.

So I started down that road. Each step requires months of healing in between. Finally I had the base inserted in my upper jaw for several months, and the x-rays showed it to be solid, so we proceeded with the next step: removing the inner threaded section that will hold the replacement tooth. This is pretty routine, but when the dentist began unscrewing it, I nearly jumped through the ceiling! Oh man, I hadn’t felt intense pain like that before!

Needless to say, that was not normal. It turns out that in a very small percentage of cases, the soft tissue grows faster than the bone, and infiltrates the implant base. This soft tissue is chock full of nerve endings, and when it got caught in the threads it hurt like hell! The only thing to do at that point is remove the entire implant material (after injecting me with lots of anaesthetic!), and start the whole process again.

So that’s where I am today: after several months of bone regeneration, they drilled into it and inserted a new implant base. Now I just need to wait several more months to see if this one is good.

Day 36: Is Plastic the New Oxygen?

Imagine that it was possible for you to observe the primordial Earth, a little over 2 billion years ago, when plant life first began to emerge. Up until then, all life depended on chemicals in the environment, such as hydrogen sulfide from volcanic vents, or simple hydrocarbons such as methane. Along comes this new form of life that can get its energy from the sun using photosynthesis. No longer tied to certain locations where they could find food, they could spread to any location that received sunlight, and populations of photosynthetic life forms explode.

This new life form came with a price, though: these creatures emitted a highly corrosive chemical as a waste product of photosynthesis: oxygen.

That’s right: before photosynthesis, there was little oxygen in the atmosphere. What little there was reacted with metals such iron, corroding it to oxides like rust.

By any definition of the word, plants were polluting the atmosphere. From that definition:

The presence in or introduction into the environment of a substance or thing that has harmful or poisonous effects.

To early Earth, oxygen was a pollutant. In fact, geologists use the sudden increase of oxidized metals in the Earth’s crust to determine when the emergence of photosynthetic life occurred. But it was exactly this sort of “pollution” that enabled the rise of a different kind of life: animals that breathed oxygen to “burn” carbohydrates and fat for energy.

Fast-forward to the present day. Human life has left its mark on the planet, and have created two materials that will likely be part of the geologic record: concrete and plastic. Concrete is relatively inert, but plastic is made from hydrocarbons, and could be a source of energy. Amazingly, scientists have already found a bacterium that can digest plastic for energy. That’s pretty amazing, considering that plastic has only existed for a century or so, which is infinitesimal on an evolutionary timescale.

So if it were possible to be present when it was happening, who would have ever thought at that time that the emergence of highly-corrosive oxygen pollution in primordial times would ever be a good thing? Yet today we certainly feel that it was, as it enabled the rise of new life forms (such as us!).

So I have to wonder: is it possible that the emergence of plastic as a nearly ubiquitous presence in the environment might result in amazing new forms of life, as happened with the addition of oxygen to the environment? It seems just as far-fetched as considering the introduction of a corrosive element would be a positive change.

Of course, we’re talking millions and millions of years, but nature has done stranger things in that kind of time frame.Such evolution would require that humans would continue to crank out plastic and dump it into the ocean for millions of years, or life that depends on consuming plastics would quickly hit a dead end.

Don’t get me wrong: I’m not advocating for plastic waste in the hope of some wonderful new life form. I feel very strongly that we should reduce out plastic usage, and recycle/reuse as much as possible. And we should be doing everything we can to limit the spread of waste plastic into the environment.

But it’s something to think about.

Day 35: Chopped Candidate

Have you ever watched the TV show Chopped? If you haven’t, it’s a competition among 4 chefs. There are 3 rounds, and after each round, one of them is chopped (eliminated), until one remains. The winner gets a cash prize. This would seem like a good way to determine who is the best of the group, right?

The problem is how the competition is run: each round the chefs are given a basket of “mystery” ingredients that they can’t see until the round begins. And more often than not, the basket contains, shall we say, “odd” combinations. One such basket contained blood orange syrup, the African spice blend ras el hanout, hot cross buns, and lamb testicles. The chefs can add other staple ingredients, but those four flavors have to be featured prominently in the result.

And if that isn’t difficult enough, there is a time limit that is always ridiculously short. The chefs had 20 minutes to create an appetizer from the basket I described above: 20 minutes to create a recipe, determine what other ingredients to add, prepare and cook the food, and then plate it for a beautiful presentation.

I must confess that I find the show very entertaining, and have watched countless episodes. And I’m not alone: the show has been running for 44 seasons over the past 11 years. But let me ask you: if you were opening a restaurant, would this be the way you would select your head chef? I would hope not! Any restaurant that would spring surprises on their chefs and expect them to deliver first-rate food in impossibly short time limits wouldn’t last very long.

Which brings me to the point of all this: if you are interviewing for a programmer, do your interviews actually determine how well they would be able to work in your team? How positive their contribution will be?

Making a candidate live code a solution to a problem they’ve never seen before in a short period of time with people watching their every keystroke is the software development equivalent to being on Chopped. I certainly hope that your work environment isn’t anything like that. So why would you think that a live coding session in an interview tells you anything about their potential?

What artificial scenarios like Chopped or live coding interviews do is test a candidate’s ability to handle stress. Personally, I’ve never had a problem with live coding, but then again I’ve never had test anxiety in school, either. I’ve seen many talented developers choke under those circumstances, but that doesn’t mean that I wouldn’t want to have them on my team.

What does it say about your company as a place to work if the bar they have to clear is how well they can handle high levels of stress?

When I first started interviewing candidates when I was at Rackspace, the standard was to have one interviewer do a live coding challenge, and another ask one of those bizarre, abstract brainteasers (“Walk us through your thoughts…”). Once again, these practices just show how nervous someone is in what is already an inherently stressful situation. That link includes a juicy quote:

These types of questions are likely to frustrate some interviewees so watch out for those who aren’t willing to play the game. It’s an interview after all and you make the rules.
Mark Wilkinson, head of recruitment, Coburg Banks

It’s all a game to him, and if asking questions with no right answers eliminates potentially good candidates, tough. It sounds like he is more interested in seeing who can tolerate being bullied than finding the best people for his company.

After sitting through some of these types of interviews at Rackspace, I campaigned internally to change these practices, because I saw some intelligent and capable candidates get flustered and end up looking dumb. I found that there are better ways to determine if someone is a good addition to your team. Perhaps I’ll elaborate more about these in a future post…

Day 34: They Grow Up So Fast

Remember that large collection of butterfly eggs that I found almost 2 weeks ago? They’ve been eating, pooping, and growing non-stop ever since.

For some reason it seems that some grow faster than others. I generally keep the very little ones in a small plastic container with their food, as it helps to keep them from wandering off. But once they get big enough (third instar if we’re being technical), I transfer them to a larger mesh enclosure where I can provide more food, and where they can eventually pupate.

About half of the growing caterpillars outpaced their siblings, and so I transferred them to the larger enclosure first. The rest went into a second enclosure a few days later. Now that first group has grown to the point where they are ready to pupate.

When they’re ready, they stop eating, purge any undigested food from their stomachs, and search for a place to attach themselves to transition to a chrysalis. In the wild they can travel pretty far – when I used to let them grow outdoors, I’ve found their chrysalises attached to plants over 25 feet away. To get to those plants they would have had to crawl down the pot they were in, up a two-foot tall stone wall, and then across the garden to the plant.

Being in an enclosure limits their ability to find an attachment site. Sometimes they climb the enclosure itself and attach to either the sides or the top (as Lazarus did), but that’s not ideal, as it makes it hard for me to attend to the others without disturbing them. So I create what I call a Pupation Station.

They are pretty simple: I find a branch with a Y-shape to provide a stable base, cut sections of branch at a slight angle, and then glue them to the base. Most of the time the wandering caterpillars find it, and choose to transition there. Here is a photo from last year’s crop of caterpillars, where 5 of them attached themselves to the branches:

So as I mentioned, the first group has already begun the pupation process. Two of them have purged, and have attached themselves to the ceiling of the enclosure. The rest are looking pretty pudgy, and I suspect that they will soon join them.

I took the above photo during a feeding/cleaning session. I remove the bundle of parsley and/or rue from the container of water, and separate the stalks with caterpillars from the rest, which is discarded. I take a bunch of fresh parsley, add the stalks with the caterpillars to it, and tie the base with a rubber band. Meanwhile I empty the glass that holds the water, as it is pretty gross from all the caterpillar poop that drops into it. I’ve started adding some round glass pieces to help prevent the caterpillars from drowning, so those have to be washed too. Then everything is carefully re-assembled and placed back into the enclosure.

Speaking of not drowning, I noticed this morning in the enclosure for the slower-growing caterpillars that one of them was partly submerged.

It looks like it had fallen down from the parsley leaves into the water, but since the glass pieces are there, it was able to crawl back up the stems to continue feeding. It made me very happy to know that I had learned from the bad experience of the past, and that adding those pieces saved a caterpillar from drowning.