What is Lichen? Why is it so cool??

On a recent bike trip to the shore of Lake Waubesa near Madison, WI I saw this awesome tree covered in this crazy greenish stuff.

Summer has returned to the northern hemisphere and I'm SO PSYCHED.

That greenish stuff on the trunk of the tree are lichens. Lichens are the coolest fungi! Lichens are also the coolest plants and the coolest bacteria! Wait...  how is that possible????

Clams' Insane Molecular Diversity

When I tell people I am a chemist the most common response is, “Oh man, I hated that in school, especially organic chemistry!” That's an unfortunate but reasonable response. Trying to understand these tiny things called molecules that are impossible to see can be kind of like learning about a never-to-be-seen dimension in which up is down and left is orange.

Thinking about chemicals can be very disorienting. Image via Andrew Lipson.

I love chemistry though because the shapes of these molecules scribbled on the chalk board actually have consequences that we can see in the world. The changing color of leaves on the approach of winter is caused by actual changes in the structure of the matter of which those leaves are made.  The effects of the diversity of molecular shapes in the world around us can actually be SEEN with our eyes!

Green and yellow leaves on the Katsura tree with the chemicals responsible for those colors (chlorophyll a and yellow-chlorophyll-catabolite, respectively). Image and knowledge via Krautler et. al.

When someone tells me they are a biologist my most common response is, “Oh man, biology is so complicated!” It seems so daunting to me to move beyond a simplistic description of aspects of life such as "chemical X results in color Y" and actually try to understand the nearly unfathomable diversity of chemicals that come together to make each living thing unique.

Not to scale. Clams are way bigger than DNA, which is way bigger than water.

I am certainly not capable of crafting a simple yet complete description of how the shapes of the molecules that make up living things contributes to those things' visible shapes, sizes, and colors.

Fortunately, where my scientific brain fails, an artistic brain succeeds. Video artist and experimental animator David C. Montgomery has created a beautiful video capturing the diversity of shapes, patterns, and colors that are present within several different species of life. When watching this video (full screen it!!), try and think about how all of the differences you see are caused by differences in the shape, arrangement, and composition of the unimaginably tiny and diverse molecules of which the living things are composed.

LIFE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Why Pee is Cool - entry #3 - "Explosive Urination" or "Gunpowder Comes from Pee!!!"

So far we have learned what gives pee its color and smell, and now we will delve into the explosive way pee has changed the course of history.  That's right, pee can be turned into an explosive!

To find out how we have to travel in our minds back to the beginning of human civilization--specifically, the domestication of animals.  One thing that large domesticated animals like horses and cows produce in bulk is urine (pee pee!).  When these animals are kept inside some sort of shelter, their pee seeps into the dry plant-less ground beneath their feet, where microorganisms turn urea into ammonia.  The little pee-digesting organisms don't stop there though, they combine the ammonia with oxygen, eventually giving rise to the nitrate ion, in a process known as nitrification.

Nitrification:

Ammonia + Oxygen →  Nitrates

or

NH₃ + 2 O₂  → NO₃^- + H⁺ + H₂O

or

Nitrification of Ammonia.  Note: animals pee out urea, but  microbes turn urea into ammonia, which then undergoes nitrification.

Why Pee is Cool - entry #2 - "Why Does Pee Smell?" or "Aroma of Life"

In Germany, nothing marks the beginning of spring like asparagus!  Running from April through the end of June, asparagus season (spargelzeit) is a big deal in Germany.  Here is me happily participating in this wonderful German tradition:

Me, about to have an asparagus aneurysm

As you may know, after eating asparagus, your pee can smell pretty gross.

Bathroom Safety Tip #1: never inhale bathroom-related vapors directly, always gently waft them

Cool Chameleons, Cool Carotenoids, Cool Colors

Check out what this chameleon can do!  Understanding how chameleons do this will help you to understand how all life on earth is connected.

Why Fire is Cool - entry #4 - Ancient Energy Unleasher

When you heat a can of beans on a campfire, you are transforming the chemical energy contained in the firewood into thermal energy (heat).  As you are in your tent drifting off to sleep and the bean-induced-fart-chorus begins, you may ask yourself where the energy in that firewood came from.  As with most energy sources, the answer is that it came from the sun!  That firewood was once a tree that was merrily pursuing its life's purpose of fashioning itself a body out of carbon dioxide, water, and sunlight, in a process known as photosynthesis.

Photosynthesis requires an energy source (sunlight), therefore the products of photosynthesis (wood, etc) can be thought to contain that photosynthesized energy.  When you burn firewood, you are essentially running photosynthesis in reverse, releasing the energy from the sun that the tree went through so much trouble to absorb.

So, fire is cool because it allows us to unleash energy from the sun in small amounts, whenever we please, regardless of when that energy first arrived on earth.  In the case of firewood, that energy arrived anywhere from a few years to a few thousand years ago, depending on how long the tree had lived.

The Llangernyw Yew, a 4,000-5,000 year old tree.

This same concept applies to anything else we burn, even fossil fuels, which is where things get crazy.

New World Plant Extravaganza!

All of these plants are originally from North or South America.  The exchange of plants, animals, and diseases between the "new" and "old" worlds that happened beginning in the late 1400s is known as the Columbian Exchange.  None of these plants existed in Europe, Africa, Asia, or Australia prior to then.

Corn!!
yes, that includes popcorn, which believe it or not, does grow on a cob

Potatoes!!
no Irish potato famine without these bad boys.  also, imagine potato-less pierogi's!?