March 24, 2011
Once again, I have taken a sabbatical from this blog. While I have been away, the earth has been shaken by both agitated tectonic plates and agitated world leaders. Also, one of science’s stalwarts, Darwin’s theory of evolution, may be agitated by the ungrateful, invasive and ugly cane toad.
After humans foolishly introduced the toads to Australia, the cane toad invasion took off. The toads spread across the continent at unbelievable speeds. And they were reproducing like mad, as well. Survival of the fittest and screw any native species in the way, right? But scientists noticed that the adaptations for speedy dispersal did not necessarily create fitter individuals. In fact, the toads that dispersed the fastest had the highest mortality rates. But those same toads only had other toads with the adaptations for speedy dispersal to choose for mates. So they reproduced.
The scientists who noticed this phenomenon call it “spatial sorting.” They claim that natural selection is still the supreme overlord of the situation since if the speedy dispersal genes stopped the toads from reproducing all together, the genes would die out. However, the spatial distribution of the genes is an important evil minion deciding which genes are passed on. If toads can only mate with other toads with the fast genes, they will be passed to the next generation even if those genes create individuals that are more likely to break their spines.
I don’t quite understand how this is different from natural selection. Cane toads are currently invading much of Australia and speedy dispersal genes are advantageous for those on the front lines. Longevity does not necessarily mean fitness as long as the toads reproduce anyway. Maybe in a hundred years when cane toads are dispersed throughout the continent, the speedy dispersal genes will no longer be advantageous and the high percentage of the genes might be detrimental to the population. Maybe then the genes from the cane toads who stayed behind and moved slower will become more dominant in the overall population. Right now, it seems like speedy dispersal genes aren’t really that bad as cane toads are thriving.
This is very theoretical and the scientists behind the study acknowledge that it is difficult to separate natural selection and spatial sorting. I like the idea because I enjoy thinking spatially. I think I need to read more on the theory to truly understand why spatial sorting might be separate from rather than a component of natural selection.
March 2, 2011
A new paper recently came out in Conservation Biology that emphasizes the positive aspects of invasive species. The authors claim that invasive species can replenish damaged ecosystems and sustain at least some natural health in generally unnatural areas. They also predict that many non-native species that are perceived poorly today will be looked upon more positively in the future.
Generally I live under the assumption that everything is more complicated than we can ever understand. Nothing is 100% bad or 100% good. In places where humans have completely destroyed everything that is natural like Washington DC,the cesspool of the universe, an invasive dandelion poking up out of the sidewalk might be a welcome sight. I also truly enjoy honey and honey bees are not from around these here parts.
But let us consider another invasive:
Bromus tectorum – The Scourge of the West
Negatives of cheat grass:
1. It is an annual grass that out-competes native grasses and lets face it, native grasses are down on their luck all ready.
2. Since it is an annual it browns much earlier than perennial grasses and therefore extends the fire season. It also has an extensive root system that sucks water away from any nearby plants. I am definitely of the mindset that fires are not always bad, but once the ground is disturbed from fire there isn’t much of a chance of anything but cheatgrass sprouting back up.
3. Wildlife and livestock do not generally call it tasty.
4. Its seeds get in your socks, are extremely difficult to remove and itch like nobody’s business.
5. It’s called cheat grass. Who likes a cheater?
And now for the positives:
Okay, I really can’t think of anything that is not facetious or sarcastic. Cheat grass is gross. Step into a native prairie and you see tons of colors, tons of species and tons of insects. Step into a cheat grass prairie and you see tons of purplish brown and you end up with itchy ankles. I understand that cheat grass can fulfill a role in the ecosystem, but it is more like a selfish toddler than a member of an ecological community. I also agree with the authors of the paper that scientists have a bias against invasives and that we need to address this bias. I also don’t think we can deny the damage invasives do to native ecosystems.
I am not a grass person. If I were to choose a favorite plant it would be a tree. But last summer I grew to love the bluebunch, fescues and grammas of the northern great plains. I can’t help but cringe to know that cheat grass and its fellow invasives are almost inevitably going to wipe out what is left of the semi-intact prairie ecosystem. Yes, it will still function, but it will function as a monoculture. Humans have created enough of those.
February 25, 2011
In honor of the world ski championships in Oslo, I think that the scientists who recently discovered a new dinosaur in Utah should considered a new scientific name. The dinosaur is currently named Brontomerus mcintoshi and nicknamed ‘Thunder Thighs’ because it has a large thigh bone to which scientists presume massive thigh muscles were attached. According to the article, the thigh muscles may have been used “as a weapon to kick predators, or to help travel over rough, hilly terrain.” Not only that, but the dinosaur has upper body strength as well, as indicated by the ‘unusual bumps’ on its shoulder blades. The researcher added, “It’s possible that Brontomerus mcintoshi was more athletic than most other sauropods… so perhaps Brontomerus lived in rough, hilly terrain and the powerful leg muscles were a sort of dinosaur four-wheel drive. Doesn’t that sound a bit cross country skier-ish?
Check out this ‘kick’ over rough, hilly terrain:
and these powerful forelimb and leg muscles:
and then tell me that Brontomerus mcintoshi shouldn’t from this day forth be called
February 21, 2011
Yesterday as I was skiing up Brackett Creek, a snowshoe hare spastically crossed the trail directly in front of me. Considering how many hare tracks I have seen off the trail, I probably have passed by multiple snowshoe hares sitting stock still under a fir tree but failed to see them because they are white and so is snow. This was the first one I have seen up at Bohart and as I said, it was running across the trail in the helter-skelter manner of hares so it was hard to miss.
Snowshoe hares are one of the cool animal species that actually change color between winter and summer. Because hair is a dead tissue, however, the actual color of each hare hair (ha!) does not change color. Instead, the hare has to shed its entire coat and grow a new one every fall and spring. The new coat color is induced by hormones reacting to the changing light conditions and changing the biochromes in the hare’s hair cells (I just can’t help myself). Luckily this can happen gradually or else we would have some hairless hares running around. As it is, it takes the hares 10 weeks to fully change color. Hopefully there are some snow patches in those 10 weeks on the front and tail end of winter, or the hairy camouflage of hares can work against them.
Despite their very cool adaptation for avoiding being eaten, snowshoe hares are an important prey species for pretty much every northern predator. Because of their population cycles, they and their mortal enemies, the canada lynx, are the classic example of predator-prey population dynamics. They are also animals who know how to pick the best habitats – snowy and northern with a good dose of elevation thrown in.
Unfortunately, in honor of my birthday last week I have to admit that I, like the hare, have some white hairs growing in. Maybe it just means that in 10 years I will be super sneaky around the trails in winter.
February 8, 2011
Sage grouse country is desolate by most standards. The large members of the grouse family live on the high elevation sage steppes of the Rocky Mountains. If you happen to want to visit a sage grouse, you will find many poky dry plants, no trees and any spectacular alpine scenery (or flowing water for that matter) you might see is generally off in the distance or in your dreams. I don’t think many people in Manhattan generally think about sage grouse planning out their strut for the annual mating call at the lek each year, but today, sage grouse made the NY Times.
Why would people even read this article about a species in a remote part of the US? Because this desolate, windy and shadeless landscape is full of flatulence of the natural variety along with some coal and oil for good measure and the last thing that the oilmen who live in their mansions in Texas and ranchers who raise sheep in the harshest climate in which sheep could possibly survive want is for sage grouse to go on the endangered species list. The Endangered Species Act is often cited as the most powerful piece of environmental legislation passed anywhere. Ever. So if sage grouse do make the list (and they probably should considering how low their numbers are) there wont be any new oil or gas wells and ranchers won’t be funded, but will be required, to make environmentally sound decisions.
If the ESA scares people/the government into protecting habitat before a species is put on the list, then great. The article, at least, made the Sage Grouse Initiative sound like a plausible alternative to strict federal regulation. It also made it sound like it was applying science to policy. WAHOO! With a reactive management plan based on results. YEEHAW!
I am still a little skeptical after seeing the vast oil/gas fields and the roads connecting them in Wyoming. The Initiative is protecting high quality habitat and providing funding for ranchers to manage their lands for sage grouse, but there is a hell of a lot of BLM land that isn’t included in the project. Maybe sage grouse can survive on a little less land, but can migratory pronghorn and mule deer? What will happen when the populations on these habitat patches become completely isolated from each other? Will the people who read the NY Times care more about filling up their tanks or about a funny-looking bird in the high desert?
February 2, 2011
I couldn’t think of a better title than the one I found in this Wired article. It is perfect. It starts scary and you think, “uh oh the carnivorous plants are going to eat me” and then you find out they EAT POOP! This is hilarious in itself until you then read that the poop isn’t just normal run-of-the-mill everyday poop, it’s from tiny bats! I love it. Seriously. If you want to discover my sense of humor, read the title of this post.
But the article is actually interesting too. It talks about the symbiotic relationship between the carnivorous plants (a species of pitcher plant) and the tiny bats (Hardwick’s woolly bat) in the marshes of Borneo. As with plants in bogs, marshes and fens across the world, the limiting nutrient for the pitcher plants is nitrogen. Carnivorous plants get some nitrogen from the insects they absorb with their acidic juices and they could get some nitrogen if they attempted to absorb the entire bats. However, the ‘pitcher’ opening of plants is smaller than the bats so they don’t fall into the pit of fly despair. They do, however, roost in the upper part of the plant, which is free of the blood-sucking parasites apparently found elsewhere in the marshes of Borneo. Not only do they sleep, but they poop and people who use guano as a fertilizer know that bat poop is chock full of nitrogen.
So the bats get a cozy safe place for their daytime abode and the plants get a meal of poop. It doesn’t sound like that good of a trade unless you are a nitrogen-starved marsh plant, but hey, if it works for them, it works for me.
On a related note, I am pumped to have 5th graders up at Bohart again. The curriculum is based on ecosystems and interspecies relationships and one of the things we talk about sometimes is symbiotic relationships. Last time my big examples were birds on bison and lichen. Just wait until I throw this one at the kids!
January 28, 2011
Women are three times more likely to have an auto-immune disorder than men. We have higher rates of asthma, multiple sclerosis and lupus. Women are also more likely to die from asthma than men. Maybe the extra X chromosome wreaks havoc on our immune systems.
Or maybe girls need to stop being made from ‘everything nice’ and get down and dirty in the mud.
A recent report links the high rates of auto-immune disease among women to the fact that overall most girls spend less time outside than boys. The report claims that girls’ playtime is more often supervised and inside than boys’ and girls clothing often is ‘not supposed to get dirty.’ Although the link between a deficient immune system and hyper-cleanliness has been well-documented, this report extrapolates the connection between gender differences in the mode of play and gender differences in auto-immune disorders. The researcher hopes that more studies will be done because of the trends she delineated from previous research.
I hope she is right, because this is something I probably don’t need worry about. Maybe rubbing poison ivy juice in my eye after playing in the dirt all afternoon was actually a good idea in the long run. Maybe not.
January 24, 2011
Last week in a marathon debrief session after a school group program my coworkers and I were discussing the ecosystem science that we taught that day. We played a game at lunch that focused on the basic needs of all animals and plants – food, water, space and shelter. I mentioned that there is one more thing that all organisms need: the ability to reproduce, or a community of members of the same species. During a lengthy discussion about how to incorporate this into the game or another part of the day, during which the devil on my shoulder berated me for bringing this up when everyone was tired and ready to go home and the angel on the other shoulder kindly complimented my dedication the education of children, my boss mentioned that we didn’t need to complicate the science too much since we were just trying to get the idea across.
Of course, I then became a little huffy about science. Mainly because I had recently read an article about researchers at Michigan State University who found that the majority of college students in science classrooms do not understand the most fundamental laws of science including the conservation of matter and the carbon cycle. The researchers were concerned, quite legitimately in my opinion, that with the basics of science, students would fail to understand more complicated system-wide problems – namely global warming.
If we don’t teach the basics of science correctly, the foundations of children’s education will crumble when they try to understand the complicated layers of real world systems. I know that we teach children at Bohart one day of the year and they paying more attention to their skis and poles than the words from our mouths. However, if they take anything scientific from their day on the trails, shouldn’t we try to make it correct? Then if they hear it again in the classroom they might be more apt to remember it.
I also recently read an article about a science program at the artsy Bard College. The college is requiring all students to take an intensive science course over January term. The president of the college says, “The most terrifying problem in American university education is the profound lack of scientific literacy for the people we give diplomas to who are not scientists or engineers. The hidden Achilles’ heel is that while we’ve found ways to educate scientists in the humanities, the reverse has never really happened. Everybody knows this, but nobody wants to do anything about it.” I am sure there are many students in the program who are unhappy to have to learn about pathogens, but exposure to science may help them to make educated decisions on important environmental and health issues. As Frank Oppenheimer said, “There are many common bonds between science and art. They both begin with noticing and recording patterns – spatial patterns, patterns in time, patterns of process and behavior. They both elaborate, reformulate, and ultimately link together patterns, in nature and meaning, which initially appeared as unrelated. Both art and science are involved with order disorder transitions and the creation of tension and the relief of tension. Both endeavors are deeply rooted in culture and heritage; both expand our awareness and sensitivity to what is happening in nature, and in ourselves.”
As in the interconnected and diverse ecosystems that were the subject of the curriculum at Bohart, I think a diverse and connected mind has a better ability to handle new pressures than a brain that is focused entirely on one train of thought. The more connections we can establish and understand, as children learning about Rocky Mountain ecosystems, as art students learning about disease or as citizens trying to understand global warming, the better able we may be to overcome environmental, humanitarian and even personal obstacles.
January 19, 2011
Not only is it finally winter again here in Bozeman, it was sunny today, I built snowforts all afternoon and after work I got to go on a long classic ski. Life is great.
Except something is out of whack.
During my ski I fell not once, not twice, but THREE TIMES. These weren’t simple oops-I-lost-my-balance-I-better-sit-this-one-out falls. These were yard sales, if you can have yard sales with non-ejectable bindings. These were animated-slow-motion-flying-appendages falls.
What could be out of whack?
Humans have multiple sensory and muscular systems working to keep our balance in check. The main organ for this gargantuan task: the inner ear. Two small sacs in the inner ear are filled with sensory receptors and small crystals in a gel. When we move our heads, the crystals slide from one side to the other and the receptors tell our brains the relative position of our heads. Another section of the inner ear, called the semicircular canals, helps us figure out when we rotate our heads. The canals are partially filled with fluid and are at right angles with each other. When we turn our heads, the fluid bends another gel filled sac and receptors in the sac send more messages to the brain.
Why is it so important for us to know where are heads are located? They are always connected to the neck unless we find ourselves beneath the guillotine. The reason is that we can’t see our heads to know where the all important brain protector is or what it is doing. Thats why we need the inner ear.
The other main organ for balance is the eye. Our eyes can see almost all of our bodies, beside, of course our heads so they send messages to the brain telling it where Mr. Left Thumb and Ms. Right Calf are and what they are doing. Finally, proprioreceptors in our muscles and tendons tell the brain how stretched or relaxed the various parts of our bodies are at a given time.
So what happened to my balance today?
My inner ear could have been a little clogged, my eyes a little dull or my balance muscles a little fatigued. Personally, I am going to chalk it all up to snow snakes. They must have come out in celebration of the new snow.
January 8, 2011
This may come as a surprise, but I skated Logger’s Loop today. I tend to avoid Logger’s Loop while skating because it is a long (3 km!) uphill that is just steep enough that I can’t V2 more than a couple strokes so it becomes a V1 slogfest. Adding to the misery that comes with anything termed a slogfest, I know that I could V2 many sections if I were just a little stronger so I end up feeling utterly frustrated with myself along with really really tired.
Luckily for me, the hurt that I felt while I was in muscle-fatigue-land could improve future skis. Generally, when a muscle is exercised to its limits, it is actually slightly injured. Satellite cells flock to the injured area and adhere to the muscle proteins. Some then morph into new muscle fiber strands so the muscle grows. Some satellite cells also add nuclei to the muscle fiber which allows the muscle to process more proteins and create more contractile cells.
However, generally endurance athletes don’t grow huge Incredible Hulk muscles. Aerobic exercise doesn’t always damage muscles like weight lifting. Instead, endurance exercise enlarges the vascular system causing more oxygen-rich blood to flow to the working muscles. It also can improve the ability of lung cells to pick up oxygen and strengthens the muscles associated with respiration including your diaphragm and that little thumper, your heart.
So hopefully my ski today, along with the dose of protein I got with my salmon dinner tonight, will make the next skate up Logger’s slightly more pleasant. Maybe I will even V2 more than twice. If not, I always know that I will have a super sweet downhill at the end of the climb and my striding skis waiting for me back at the lodge. I really do love striding up Logger’s.
And here are some examples of skiers who can probably V2 up Logger’s!