shut up you stupid little birds

Sunset outside my bedroom window

Here in Alaska, the days are starting to get pretty long. I crawled into my bed last night and watched the most beautiful sunset- at about 9:45 at night. That post-sunset glow lasted until about 11:00. Then, I woke up this morning to the sound of birds chirping and the world filled with sunshine- at 5:00 AM. Starting my day off with the thought “shut UP you STUPID LITTLE BIRDS” is becoming pretty routine.

Even down south in the lower 48, there are noticeable differences in day length in the winter versus the summer. Days are longer in the summer, shorter in the winter. I used to look forward to Louisiana summer days when I could stay out waterskiing until 7:00 at night. I’d have just enough time to come in to shower and relax my tired muscles, then walk back out to the seawall to watch the sunset around 9:00. These hot summer days were very different those cold winter days of high school, walking in from school at 4:00 and it already starting to get dark outside.

So what is the deal with the changing day lengths throughout the year anyway? Why do we here in southeastern Alaska get mostly dark with a few hours of light in the winter, and vice versa in the summer? Why do the poles get 24 hours of one or the other? Why is it less noticeable as you approach the equator?

The earth is leaning. The axis around which it spins is tilted. Towards the sun, away from the sun, you ask? Well, that depends on what time of the year it is.

We earthlings make one complete trip around the sun each year. During the summer, the northern hemisphere is leaning towards the sun. By the time we’ve made it to the other side of the sun in the wintertime, the northern hemisphere is leaning away from the sun. The result of this lean is that certain parts of the globe spend a little more time in the shade than others, while others spend a little more time in the light. This is a hard thing to visualize, so let’s turn to some pictures.

Shadow zones in the winter time

In the picture above (set in our winter time), you can see that the North Pole stays in the shadow of the earth. Areas a little lower, like Alaska, skim into the light just long enough for the sun to peak over the horizon. This trend continues to weaken as you approach the equator.  The equator gets 12 hours of day every day, all year. Once you get south of the equator, then you’re spending a more and more time in the sun until you approach the South Pole. It’s summer there, getting 24 hours of light. But just wait 6 months, and the roles will have gradually reversed.

Light zones in the summer time

We’re in that role-reversal phase right now. The summer solstice, June 21, marks the northern hemisphere’s maximum “lean” towards the sun- the longest day of the year. After we get past that, the days will start getting shorter as we head back into the dreaded shadow zone. Living so far north, this time of the year drives me to embroider after work and watch Lord of the Rings, in my very own vitamin-D depraved Gollum-like transformation. By the time March rolled around this year, I was turning my nose up at taters and losing pigmentation.



Luckily, sleep masks and blackout curtains help during the summer. Socializing and reading help to resist the call of the One Ring in the winter. As they say, life is a series of tradeoffs.

I took this at noon one day in November, my precious.

spermy prom hair

Last Saturday, I had the pleasure of accompanying some folks as they caught hooligan- these little silver fish that are currently spawning here in the river. I helped to bag them up and in the process, got covered in their sperm (I couldn’t be mad- we did interrupt them mid-spawn with their little zippers down). Afterwards, I tagged along to drop by the local high school prom to check out the dresses (and seeing as I was super excited about this, I’d say I’m adjusting well to small-town Alaskan life). But the highlight of the weekend was being able to tell my mom the next day on the phone “last night I went to the prom and got sperm in my hair.”

Currently, these hooligan fish are swimming up the Chilkoot River here. They’re pretty little silver fish with tones of pinks and purples. They’re pretty general looking, which makes this occasion a perfect opportunity to relay a little general fish morphology.

Fins

Hooligan fins

Fins are the evolutionary answers to fishy locomotion. Pectoral and pelvic fins project from the body and can move in a rotational manner, acting as little steering arms for the fish.

The dorsal fin can occur in one part or two parts, with the more anterior fin always being the primary one and the back one usually being smaller and squishier. In the case of the hooligan, there are two dorsal fins. The dorsal fin(s) act as sails for the fish, slicing through the water with lateral surface area that pushes against the water on either side of the fish. This keeps the fish from tipping over, keeping it right side up. The anal fin functions in balance as well, in charge of more refined adjustments to keep Mr. Fish from tumping over.

Lastly, the caudal (caud being latin for tail) fin is the big daddy in the back that swings from side to side to move the fish forward.

Lateral line

You can peer into the water and see these hooligan swimming against the current in their little groups. They seem to almost have telepathic abilities- knowing and reacting  instantaneously to what their fish friends are going to do. Have you seen those nature shows that show schools of fish all turning and darting in what seems to be perfect unison? How do they do it?

When you look at fish, you’ll notice a faint line that runs down their sides. This is called the lateral line. Lateral lines are actually a series of nerve clumps that act as a composite sensory organ. On the surface, the lateral line is a series of sensory epithelial cells that hook up to the underlying nervous system, which translates the sensations felt by the surface cells to electrical impulses that are sent to the brain. These sensations are caused by minute pressure changes in the fish’s immediate environment. The flick of a neighboring fish’s tail, the opening jaws of a nearby predator, or the creeping legs of a delicious crustacean- the lateral line allows all of these things to be sensed without being heard or seen.

Gills

Gills are NOT underwater versions of lungs. They are entirely different structures from different origins, but do have the shared function of oxygen acquisition. In fact, they are quite superior in this area, what with their countercurrent oxygen exchange and all. Just looking at a fish, you usually don’t get a glimpse of these delicate, feathery gills. They are covered up and protected by a bony covering called the operculum. If you were to snap this off (of a dead fish only, don’t be mean!), you could then see the feathery, vessel-laden projections that serve as oxygen exchange sites for the fish.

So even though fish are slimy, they’re still worth getting to know. Living underwater presents a whole different set of challenges- but not to worry. These little guys have got it covered. Much like I was in their sperm.

wear thick panties just in case

After I graduated few years ago, I was working at a national park and living in a beautiful country house out in the middle of a Louisiana cornfield. It was a historic home, built in the 1840’s. I’d crawl into bed each night, surrounded by memories of generations of Creole culture. It was a beautiful experience. But one thing about a rural Louisiana home in the summer: bugs. Lots and lots of bugs.

Bugs are not beloved animals. Of course, there are entomologists and naturalists who find friends amongst the arthropods. And then there are the moth-loving Buffalo Bill types (it puts the lotion on its skin or else it gets the hose again). But most people either feel unkindly towards or downright terrified by our jointed, exoskeleton-bearing cousins. Spiders don’t bug me so much (see what I did there?), but put a roach or flying insect in my room, and I will immediately start crying like a girl. I appreciate them when viewed through glass or in a book, but for the love of all that is holy, keep them away from me.

I was climbing into bed in my little summer home one night, exhausted and ready to konk out. All of the sudden, a horrible, stinging pain hit my right ass cheek. I flew out of bed, and lo and behold: a red wasp was buzzing around the bed. It had crawled in between my sheets and was waiting for my bare hiney to climb into bed before stinging the living daylights out of it. I couldn’t sit for 24 hours after that horrible incident.

(Wikicommons)

Not long after that, I was reading before bed when “buzzzz buzzzz,” a humongous, black, loud, fast, and terrifying cicada started flying around the house. I mustered up all my courage to approach the beast with a broom. I tried to beat it to death- didn’t work. So I cornered it and drenched it in wasp spray. The monster subdued, and certain that it was dead, I put it in the trash. I fell asleep soundly, knowing the nightmare was over.

Sometime during the middle of the night, I was stirred awake by a sound that struck terror in my heart. The beast was somehow still alive, making its sound from inside the trashcan. Panicked, I put the entire trashcan outside on the porch, locked the door, got back into bed, and put a pillow over my head. Rocking back and forth in fetal position was not enough to put me to sleep that night.

Since then, I’ve felt a little guilty about my behavior towards this cicada. I’ve learned a little more about them since. They aren’t so bad. Yes, they still strike fear into my heart, but it’s not their fault. And their calls are perhaps one of the most comforting sounds in the world to me- it takes me back to porch-sitting, sweet-tea drinking, ceiling-fan spinning summer sunsets back home.

One particular genus of cicada has a fascinating lifecycle. Magicicada lays its eggs in tree bark. After a few weeks, the little nymphs crawl out of the nests, down the trees, and underground, where they stay for 17 years. In the soil, they spend their time maturing into adults. Long, sub-terrenean incubation periods are not uncommon for cicadas, but Magicadas are special because theirs are synchronized. This means that instead of a batch emerging each year, each generation emerges at the same time. For a few weeks, this huge population of newly emerged adults breeds like crazy and then dies. When you figure in the 17-year incubation period, it means that every 17 years, a huge emergence of horny cicadas occurs. And folks, 2013 is one of those years.

Mmmmm.

In a few weeks, the eastern seaboard will be covered with Magicicadas of the Brood II (several colonies, or broods exist across the United States). My good friend from Virginia enlightened me to the hipster culture surrounding this occurrence. She told me that people like to dare each other to eat them and that they taste like “cold, canned asparagus.” I know: oh my god.

What a strange event this seems, millions of bugs coming out of the ground all at once. Literally, all at once, in a single night. And so many! Densities have reached up to a million and a half PER ACRE. It’s truly a massive invasion. Why in the world would this genus of bugs have such a drastically different lifecycle from even its closest cicada relatives?

This is a strategy called predator satiation. You see, these cicadas are prey species. They are eaten by birds, raccoons, spiders, lizards, you name it. But by occurring in such massive bursts, predation can’t put much of a dent in their numbers. Predators can eat until they can’t fit another bug in their mouths and the Magicicada population is relatively untouched. Predators love these kinds of reproductive events- they absolutely gorge themselves, eating until they are in a stupor. Other animals exhibit this sort of reproductive strategy in coordination with predation (salmon runs satiate bears), but this Magicicada business is truly extreme.

Can you imagine being a Magicicada? You spend seventeen years growing underground, only to emerge for a few weeks to have sex and then die. I mean, it seems more reasonable for things like gnats, whose entire life spans no more than a matter of days. But an insect, living longer than your average dog, and accomplishing no more than reproduction during that span is remarkable.

Here’s to wishing the Magicicada Brood II luck in its impending emergence. They may be kind of icky, but bugs are really cool. That being said, I hope there is not a wasp, or a cicada for that matter, waiting in your bed for you tonight. Wear thick panties just in case.

Here’s a great, interpretive website that can tell you more about these little suckers.

http://www.magicicada.org/magicicada_ii.php