Friday, May 24, 2013

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.

Saturday, May 11, 2013

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.

Sunday, May 5, 2013

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

Sunday, April 21, 2013

cut in half and slightly souped up


There are certain advantages to being a man. More upper body strength means you don’t have to find someone to help you lift the flat tire you just changed all by yourself into the trunk, even though you know how to do the whole thing by yourself but just aren’t strong enough to pick up the dang tire (what, I’m not bitter). Negotiators take men more seriously (not saying it’s fair, but it’s true). Men are statistically way less likely to be mugged or assaulted. But at the end of the day, men are inherently lacking in an area that women aren’t: genetic material.
Female allosomes on left, male on right. Notice the DINKY,
 LITTLE, Y. (http://www.brusselsgenetics.be)

You have 23 pairs of chromosomes- one of each pair coming from one parent. One pair represents your allosomes, aka “sex chromosomes.” If you’re a boy, you got a “y” chromosome from your dad and an “x” chromosome from your mom. If you’re a girl, you got an “x” from your dad AND an “x” from your mom. So, girls= xx and boys = xy.

That Y chromosome is really key in determining sex. It is way smaller than the X chromosome, and doesn’t really carry too much information on it aside from the most vital male-determining genes. It contains a gene, called the SRY gene, that “turns on” maleness/testosterone production. You see, being female is like the default condition. The presence of a y chromosome lays the groundwork for being male, but the activation of its SRY gene is what actually drops the ball(s). (Which, by the way, are really ovaries that were told to descend and produce sperm by the SRY gene). So, morphologically, all embryos start off as female and then are changed into male once the Y chromosome kicks into action.

The X chromosome carries way more DNA, including sequences that are not directly sex-relevant.  Yes, there’s DNA for instructions on building ovaries and eating Ben and Jerry’s once a month (don’t forget, men have this too on their X chromosome, but that Y turns on the maleness that covers up the female condition). But there’s also genes for more unfortunate things like the recessive male-patterned baldness and colorblindness.

Women carry these genes all the time. But since they’re recessive, the trait is not expressed unless a very unlucky lady happens to get them on BOTH her X’s. And that’s just not very likely. But if a female who has colorblindness in one of her X chromosomes gives that X to her son, he’s screwed. That scrawny little Y from dad doesn’t have enough punch to combat the trait like a girl’s extra X would. This is why color blindness and male-pattern baldness are almost exclusive to men. Since he got the X from his mother, he knows that one of her parents is responsible. If it was her dad, he will have expressed the trait. This kind of inheritance is called sex-linked inheritance.

So really, an XY is just a cut-in-half and then slightly souped-up version of an XX. Ladies, we may not have enough testosterone to lift a tire into the trunk, but we have enough DNA to keep colorblindness and pattern baldness at bay. We win… this one.

Tuesday, April 16, 2013

i need more sticky notes


I work at a small natural history museum where we receive lots of museum catalogues. Last week, a copy of the 2011 “Bone Clones” product catalog found its way into my hands. Let’s just say that I’ve spent way too much time flipping through it and putting sticky notes on pages that have cool stuff. They've got all different skulls from all different humanoid species. They've got bird skeletons. They've got eggs. They've got reptile and amphibian skeletons. They've got extinct animal bones. I can't even handle it.  I’m going to have to buy more sticky notes.

I love bones. They tell stories- yes, stories in the cheesy “NCIS” forensic way- but they tell more expansive stories too. Bones have been our clearest windows into our evolutionary past. With technology advances, DNA sequencing is becoming the front runner. But bones, I think, will always be the most tangible (and my personal favorite) way to unravel our past’s morphological secrets.

I would like to share with you a few of my favorite human bones- all of which are part of the spine. Our spine is important in that it fostered the major changes in our posture when we became tetrapedal land animals, and then eventually bipedal humans.

Atlas (wikicommons)
The top two vertebrae in your spinal column hold special significance. At the tippy top of the spinal column is your C1 vertebra (first cervical)- known as the atlas. Right below it is the C2 (second cervical) vertebra, called the axis. These two vertebrae are shaped in a way that allows for way more movement than other vertebrae. By articulating against the skull and each other, these two bones allow you to nod and turn your head. Notice how the Atlas has two contoured dips where the skull rests and may articulate, rather than a fused spinal-cerebral junction like you see in fish. (Poor fishies can't nod yes or no, can they?)

Axis (wikicommons)
Way back when we were fishies on our way out of the seas, emerging land animals like Tiktaalik would hide from predators in the shallows. But our fish predecessors were not well-built for air-breathing in the shallows. To make air breathing easier, nose holes migrated to the top of the head and the atlas began to form, allowing it to tip its head up and out of the water. And so, we left the water for drier prospects. As life diverged on land, predatory and prey niches were filled and binocular vision developed, moving eyes to the front of the head and limiting peripheral vision. The Axis stepped in to allow for more side-to-side head movement, allowing for more efficient predation AND predation evasion.

Hyoid (wikicommons)
Not far from your atlas and axis hangs the hyoid bone. The hyoid bone is not the most well known, because it is often missing from skeletons and skeleton drawings. This is because it is unconnected to the rest of the skeleton. It essentially floats in the throat area, suspended only by muscles and ligaments. If you press on the underside of your chin and back a little, that’s about where it is buried. The hyoid bone itself is an evolutionary descendent of a gill arch- a cartilaginous support structure found in the gills of fish. In us, it serves as an anchor for the back of your tongue so you can say words. (On a cheesy NCIS note: the hyoid bone almost never gets broken unless someone tries to strangle you. So fractured hyoid = homicide by strangulation.)

Coccyx (wikicommons)
The coccyx, or the tailbone, is the very last bone in your spine. It’s more of a “bone unit,” actually consisting of several fused vertebrae. Way back in our primate histories, we had tails. As we climbed out of the trees and onto the plains, they disappeared in our current primate lineages. But they left the coccyx remnant- hence the name “tailbone.” Now they’re only good for bruising, breaking, and the occasional vestigial-tailed mutant baby.

If I could choose one art project to work on for the rest of my life, it would be cataloging and illustrating every single vertebra in every major vertebrate family. They themselves are strange little works of art, their contours and projections both beautiful and telling of their function.

But if I don't ever find a life-long job opening for "vertebrae drawer," I'll just name my kids Atlas, Axis, Hyoid, and Coccyx. They'll hate me forever, but man, what cool names they'll have.

Friday, April 5, 2013

lavender candles and toilet handles


Today was one of those wonderful days. It was sunny and gorgeous outside, I got a ton done at work, and I had one of those rare but oh-so-satisfying, single-girl, “I just fixed something that broke without having to ask for help” moments when I installed a new handle/lever arm in my broken toilet. Small victories, people.

I wish you could smell
through the internet.
The best part of my day was undoubtedly receiving a care package (from my soul-twin, of course) that was full of goodies like herbal tea, cozy socks, fancy office supplies, facial masks, and chocolate. Nestled in this little box of heaven was this lavender and eucalyptus aromatherapy candle (left).

Lavender has been used in a medicinal capacity for millennia.  It helps aid relaxation, can ease dermal irritations, alleviates pain, and acts as an antiseptic. It’s easy to grow at home, and smells absolutely divine.

Once upon a time, doctors noticed something fishy going on with young boys and lavender oil. Several pre-pubescent boys were experiencing gynocomastia, clinically known as “boob development.” The onset of this breast development coincided with all of the patients’ use of a topical ointment with a principal ingredient of lavender oil. Was lavender oil inducing estrogen production in these kids?

Lavender in bloom (sloatgardens.com)
Yes, come to find out. A study by Henley and Korach (2010) confirmed that several essential oils, the most common of which being lavender and tea tree oil, routinely cause “endocrine distrupting activity”- aka they mess with your hormones. Specifically, your sex hormone estrogen. They considered both estrogen production and the different estrogen receptors in mice to see at what level the lavender was acting. They found that lavender exposure actually enhances expression of estrogen-producing genes. This means that lavender actually causes your cells to read the DNA blueprint for estrogen at a greater rate, flooding the system with excess estrogen.

Men have estrogen too, just as women have testosterone. They just have them in different proportions. So, both genders are vulnerable to the estrogen-spike that lavender exposure can initiate. Naturally, it is more noticeable in the sex with lesser estrogen. Luckily for those poor kids in the study, the gynocomastia subsided with decreased lavender exposure. Phewph. So if you are a guy, don't go shooting up with lavender oil unless you want to start wearing a bra.

Here’s to fixing stuff on your own, having wonderful friends who take care of you from 3,000 miles away, and hoping that my new candle will induce gynocomastia to help a sista’ out if ya’ know what I mean.

Or at the very least, that it will induce some aromatherapeutic relaxation while I soak in my tub wearing a facemask and listen to Enya, all the while admiring my new toilet handle out of the corner of my eye.

Wednesday, April 3, 2013

Myer-Briggs voodoo magic


Have you ever taken the Myer-Briggs personality test? It’s the one that gives you four letters, each representing some part of your personality. We had to take one our senior year of high school as a way to help point us to potential career choices. The questions seemed completely arbitrary- i.e. Do you like to sit to the left, center, or right of a room? I remember thinking what a crock it must be as I finished it up and turned it in.

A few weeks later, our teacher hands us back our sealed envelopes with our results. I read mine, astounded that this test understood me better than anyone I’ve ever known. Well, better than anyone except my best friend Ashley- who coincidentally sat right behind me. (Ashley and I call each other “soul twins”; in a world where we feel quite different than most, we just get each other). I spun around to discuss the results of this voodoo magic with her. And would you believe it, she and I scored the exact same personality type. The rarest type at that- making up 1% of the population. If that doesn’t verify a friendship, I don’t know what does.

In previous posts, we’ve talked about how behaviors evolve. But personalities- where do they come from? Are they genetically linked? If so, did natural selection act on them during the development of our species? Did personality evolve?

I did some research into the evolution of personalities. There are a bunch of scientific papers on it. In general, most of them say that there is evidence that many personality traits are genetically linked, but there are so many variables involved that it is an abstract and a “poorly understood” mechanism. Translation: it's likely. But we can’t figure it out yet.

Somewhere in our history as tribal animals, social hierarchies emerged. Maybe, each tier in the social hierarchy can be thought of as a niche, and each individual as a particular species. Individuals had to divergently evolve to reduce competition for a singular niche, making it easier for each social role to be filled.

What if everybody in a tribe was super outgoing, or overly dominant? There would be fights and pissing contests all the time- that wouldn’t work very well. What if everyone kept to themselves and didn’t share ideas? That wouldn’t work very well either. Is it possible that this could have been the groundwork for the evolution of personalities? Populations of humans with wider ranges of temperaments and social roles were the most successful?

Who knows? Maybe. Even if it was, then a lot has happened to complicate and deepen the human personality since then.

This post answers zero questions, and raises a bunch. But I kind of love it when science hasn’t yet figured out something. Not knowing things allows us a sense of wonder that answers don’t. It’s amazing how different people can be, and thank goodness for it.  My sister and I, for instance, are as different as night and day. But I couldn’t have asked for a more complimentary sibling counterpart. And I know that I could never marry someone just like me. We’d read books on weekend nights and never be forthcoming with our thoughts or feelings. Regardless of how they came to be, personalities help make our world go ‘round.

If you haven’t taken the Myers-Briggs test, there are a few online. They’re not as thorough as the official one, but I at least scored the same on both. After getting your score, consider: if you had been Tuk-tuk in the early ages of human, what social role might you have filled?

Here are the links to a couple tests: