Thermodynamic Witchcraft

Story time, everybody!

So, right now I’m on a field research team working on the prairies of Colorado. Also right now, the temperature out where the deer and antelope play is stuck in the nineties. Needless to say, I bring a lot of water to work. But since I do not want my water to warm up too quickly and start tasting like old bath water, I freeze it overnight. This is very nice, but I can’t drink completely frozen water. Solid ice is just about useless when you’re thirsty. It needs to melt. Luckily, water (and everything else) has free energy. Free energy (represented by G) is a component of the total energy of a system that can do work at constant pressure. The system is the object or react in question and by work I don’t mean that free energy has a desk job or something. In physics, work is the displacement of an object by a given force. Push a book across your table/desk/park bench with wifi and you can say that you are doing work on that book. This also means you are transferring energy to the book, causing it to move. It’s like witchcraft. Minus the hoods and black goats.

Such evil things.

ANYWAY, if free energy changes, the system/my water bottle is undergoing some kind of reaction. If the change in energy is negative, that is, energy is exiting the system, then we say that the reaction is exergonic. Such reactions are also called spontaneous because they produce product under a given set of conditions and without any work until a reaction reaches equilibrium. However, when the change in energy is positive, energy is entering the system and we say that the reaction is endergonic. It is also non-spontaneous because the reaction won’t proceed toward product production without work being done. So where is my water bottle in all this? It is sitting in the hot Ford Explorer, and given those conditions it doesn’t have to do any work in order to melt. The bum.

Exergonic and endergonic reactions do not necessarily involve things heating up or cooling down. Explosions are a great example of exergonic reactions and they involve (quite a lot of) heat, but protein synthesis is an excellent biological example of an endergonic reaction that does not involve a drastic temperature change.

Now if you’ll excuse me, I’m going to go set up another exergonic reaction in my glass.

Cheers!

Sources

Hoffman, Kurt. “Work and Power.” Physics. Whitman College. Walla Walla, WA. 2011. Lecture.

Sholders, Aaron. “Thermodynamics.” Biochemistry. Colorado State University. Fort Collins, CO. Jan 2013. Lecture.

 

EDIT: Got my endergonic/exergonics confused with regard to ice melting. Fixed now!

Cue Tumbleweed

OK! I am all moved in to my new home in Colorado and having switched my license, caught horny toads and been stuck by cacti I think I can say I am well settled. This means a return to a mostly regular posting schedule barring sunstroke and/or infectious disease.

To start/restart, I’d like to discuss some of the science of color. I’ve gotten into color producing cells previously (See Wolf Bite), so you know a little of the “how” but time now for a bit of “why”.

WHY

If color did not matter, the world would look like a box of crayons threw up, that is, not pretty. Unless of course you are color-blind and/or like that sort of thing. However! Color does matter, not only are certain compounds always certain colors (chlorophyll, sulfur, etc), but colors have certain properties. For instance, blue light travels further in water than any other light and red light travels the least. As I’ve mentioned previously, there are many benthic and/or deep sea fish that can’t even see red light as a result of this phenomena. So there are lots of benthic fish about that are red or brown, making them virtually invisible.

This gets into one of the uses of color: camouflage. Besides this there are toxicity warnings, mimicry, mating displays and heat regulation. These can all work together, but heat regulation has some of the greatest influence.

So another color property you may all remember is that black attracts and white repels light (and, as a result, heat). Perhaps you learned this in conjunction with building a solar oven in grade school science. I’m certain this was not just me and my hippie grade school. But in nature this means plants and animals in cooler climates will be darker while those in hotter climates display light colors. Sea shells are a great example. Tropical sea shells are all dainty and white while temperate sea shells are dark and dull. Yet what about all those white arctic animals? Arctic foxes, wolves and hares all wear puffy white coats in the snowy Winter and sleek black coats in the Summer. So camo trumps heat regulation? Nope. If any of you lot ski, you know that you have to wear sunscreen because enough heat reflects off of the snow to cause sunburns. My dad has a story about getting a sunburn inside his mouth. He would have to explain that accomplishment. Probably too much ecstatic yelling down the slopes. Anyway, imagine tromping through a Winter wonderland in your thick, black fur coat. You would stick out like a sore thumb AND you’d sweat your eyeballs out. So camouflage and heat regulation in this case work hand in hand.

What about the tropics where the flora and fauna display colors like it’s going out of style? Look at the plants, first. Much of the leafage HAS to be green to absorb and process light for photosynthesis, while the flowers and fruits need to attract pollinators and frugivores (to pollinate and spread seeds, respectively). So the flowers and fruits need to stand out. White would stand out, but again the flowers and fruits contain necessarily colorful compounds.

Now, since the environment is colorful, tropical camouflage is not restricted to drab greens and browns. Add to the mix the various and eccentric mating displays of tropical birds and BAM colorful critters. Except the mammals. The mammals are sort of boring.

Fossa can’t help that mammal color producing cells aren’t fabulous. Fossa would like to be fabulous.

Sources

Source
–. “The Deep.” Blue Planet. BBC: 19 Sep 2001. DVD.
Schrope, Mark. Nov 2007. “Lights in the Deep”. Nature. 472-474.
Yancey, Paul. 2011. “Deep Pelagic.” Marine Biology. Whitman College. Walla Walla, WA. Lecture.

Zebra photo credit Chris Johns. Fossa credit “Jack the Lizard”.

Mustelid-day 3: Your Old/New BFFs

I swear that I am getting CRAZY stuff done when I’m not here. CRAZY. I swear.

Ahem…

Anyway! Where was I? Ferrets, right?

Right.

Of the three ferret species in the world, the black-footed ferret is the only one native to North America. And we kind of ruined its shit.

Formerly, our little (“little”, they can be up to two feet long) BFFs of the prairie, rocked the nights away (they’re nocturnal) on the mixed grass and short grass prairie scene. Literally. They are lively little suckers.

They are also really into the underground scene (they’re fossorial). Tunnels are their THING, man. Not their tunnels, though, prairie dog tunnels. Why tire your stubby little paws digging when a few hundred prairie dogs can do it for you? Exactly: Prairie Dog Construction Crew. Plus our BFFs can eat the crew when they’re done. But our BFFs depend on this kind of convenience; a pair ferret needs around 10,000 prairie dogs within its territory in order to survive. Good thing they’re usually solitary, but still; DAMN.

Now, to get at where humans come in to ruin everything. As farms blossomed on the lone prairie, many prairie dog towns were tilled into oblivion, and most of our BFFs with them. Where once there were hundreds of millions of prairie dogs, now there are, like, 20 million. A sizable dent in their numbers, but not so bad, eh? Well, the tilling that only dented the prairie dog population, endangered our BFFs. They now occupy less than 2% of their former range. Also, since there are still more than plenty of prairie dogs to go around, it means that those guys are running amok on the prairie. Their other predators are just not picking up the slack. Solution: captive breeding programs and reintroduction. Simple? NEVER. This kind of shit is never simple. Just ask a Montanan about wolves. Anyway, the issue is controversial because ferrets require prairie dogs (SO MANY PRAIRIE DOGS) and that means that the same people that want prairie dog population control will have to leave those P-Dog towns alone for our BFFs to do their thang. If this doesn’t seem like a big deal, imagine you are a rancher and prairie dog holes are breaking your cows’ legs. Yeah, it’s not going over well.

This isn’t to say there is not a solution! We just need to get along, and why can’t we all just get along? We have to, for our BFFs.

Sources

–. 2011. “Ferret Facts- Animal Profile.” Black-Footed Ferret Recover Program. Black-footed Ferret Recovery Implementation Team. August 1, 2013. < http://blackfootedferret.org/animal-profile&gt;

Cogger, Harold G., Joseph Forshaw, Edwin Gould, George McKay and Richard G. Zweifel. 2002. “Carnivores”. Encyclopedia of Animals. Barnes and Noble Books, New York.

Krebs, Candace. 2013. “Ferret’s Link to Prairie Dogs Underlies Opposition.” La Junta Tribune Democrat. August 1, 2013 < http://www.lajuntatribunedemocrat.com/article/20130726/NEWS/130729959&gt;