Humans and their Tall Tales of Snakes: Science to the Rescue

                Snakes.  Personally, I am quite found of them.  I like the large venomous ones that have a built in rattle.  I like that they can periodically refresh themselves with a good skin shedding that keeps them looking as young and vibrant as ever.  I like how their scales cover their surface like a roll of sequins.  Snake fondness could be the next fad with a little help from everyone, and science can help.

                I was just reading a study called “Defensive behavior of cottonmouths (Agkistrodon piscivorus)” by Whit Gibbons and Mike Dorcas and am reminded how we scientists can put myths to the test quite literally.  It’s one thing for snake lovers to say that people shouldn’t worry about venomous snakes and how unlikely they are to actually bite a person.  But people seem very confident that venomous snakes, in particular, are prone to chase a person down for a little venom therapy, just for funsies.  Sure, we can say “Approximately 8000 of the 310,000,000 people in the US will be bitten by a venomous snake—or ~0.026% of the population.” Or that “There are typically 12 or fewer deaths in the US per year for venomous snakes, or ~12/310,000,000, which is 0.0000039% of the population.”  Or even in our most confident voice “In contrast, there are roughly 40-50 deaths by lightning strike and 90 deaths by motor vehicle crashes each year in the US.  Come on people, evaluate the risks properly.”  But, nothing is quite as convincing as a nice hypothesis-driven study.  And, the study by Gibbons & Dorcas (2002) suggests that you are most likely to be bitten (and therefore in some unlikely cases die) by a venomous snakebite if you pick up and harass the snake.  So, I had to share the data:

                They had three treatments:  1) stand beside a snake (in snakeproof boots) while touching its body; 2) step on the snake midbody without injuring the snake; or 3) pick up the snake midbody with a pair of snake tongs that look like a human-hand and arm.  (Would love to see a picture of those, personally.)  And these (above) were the results they found.  Most of the snakes that bit were picked up with the human-like hand and had also been stepped on—so the more harassment, the more likely the snake was to bite.  Even still, 60% of the snakes did not bite when picked up.  None apparently chased the researchers when they were done with the study.  NONE! 

                So, if you do not want to be bitten by a venomous snake, then do not harass them or pick them up or kill them, just stand back and admire them.  Every living creature could use a little more admiration.  Myself included (husband, are you listening?). 

Just a Couple of Nice Days in the Field

We are having such gorgeous weather in wild & wonderful Ohio this week.  (I know weather is the stuff of old people, but I turned 40 this week and, therefore, must speak of gorgeous blue skies.)  Yesterday, I was out with my herpetology class looking for, well, herps, of course.  There’s a good crop of herpers in this group (too bad they are not reading this, because I’m sure that comment would give them a warm, fuzzy feeling).  We saw a few lovelies including the southern two-lined salamander, which we saw in all sizes, small larvae to big and chunky adult.  Such a lovely surprise to turn over a rock and find a salamander or snake.  Of course, we are turning rocks over for this very reason, but it’s still kind of like buying a lottery ticket…you don’t win every time. 

We also found a few snakes under some of those rocks—queen snakes and small northern water snakes.  A number of snake whisperers in class this year that seem to find them no matter where we are, but these were all hanging out at the water’s edge. 

Today I was out in the field for a bit checking my terrestrial pens. Notice anything?

  

I raised these northern leopard frogs from tadpoles in ponds and then placed them in these terrestrial pens.  As tadpoles, they were exposed to an insecticide at 2, 4, 6, or 8 weeks after hatching and we’re following them in the terrestrial environment to see if there are long-term effects from early life exposure.  The pens are only about 6 feet by 6 feet, but these frogs are hiding Houdini’s in the grass.  I’ll hop into a pen and see a frog, but I think they have a secret hidey-hole or two.  Fortunately, there’s one nice big hidey-hole, which we elegantly call “the central pit,” and when they are in there I can catch them better than a frog can catch a fly.  Aren’t they gorgeous?  This is the last part of a very long three year study, which has had more than the normal numbers of snags.  I’m keeping my fingers crossed for something really, really, really interesting.  However, even if it’s really, really, really not interesting, they still had me out on a nice 60 degree F day working my Jedi reflexes to catch these lovely beasts.  Science is good!

Your Inner Fish, My Inner Fish

Finished a good science read this morning by Neil Shubin, Your Inner Fish:  A Journey into the 3.5-billion-year History of the Human Body.  You should check it out.  Shubin’s the guy who discovered Tiktaalik, the missing link between fish and tetrapods.  Here’s a picture of that beast:

 I know, Tiktaalik is quite a doll.  Paleobiology-types were so excited about this fishapod because it had a wrist and a neck, as well as a number of characteristics associated with amphibians, the first tetrapods, likes a flat head with eyes on top of the head.  But, Tiktaalik is still very fish like with its fins and general fishiness.  Your Inner Fish starts out with Shubin’s stories about the discovery of this and other fossils and how paleontologist use geological maps to make educated guesses about where they might find certain types of fossils.  Good field stories.

Shubin makes connections between the limbs and hands of all tetrapods with their earliest fish ancestors.  He covers the connection early biologists make in the 19^th and 20^th century between life forms based on studying embryonic development.  And he brings us to the amazing discoveries (and potential for discoveries) in the molecular age—how you can find genes that build bodies in mammals in a very similar form in all sorts of other animals and even choanoflagellates, our protist ancestors.

Some of my favorite things from the book:  Teeth appear to have arisen before skeletons and the first skulls were very tooth like.  He called this an “inconvenient tooth,” which I think you’ll agree is hilarious.  Our earlier ancestors had gonads by their heart (like sharks today), but they have since traveled to the nether region, which causes some problems especially for males who are more susceptible to hernias thanks to the gonad’s peregrination.  The end of the book talks about how the design of the early ancestors that has been tinkered with over time causes some design issues.  There are more than a few good pieces of information to have in your toolbox next time evolution comes up with your fundamentalist relations who try to deny the fish (and sponge) within. 

If you haven’t picked it up, it’s worth a read.  My intro biology students should love it and it made me wonder if Shubin’s book might be the preferable way to cover animal diversity.  Also a must read for med-types!  Shubin has some nice descriptions of nerves leaving the skull and explaining why they wend the way they do.  The interconnection between our lives and the lives of all biodiversity are pretty awe inspiring, and Shubin’s book definitely turns on the awe-o-mometer. 

What's Not For Dinner

  

A visit From the Ocean Doctor is better than a visit to your medical doctor.  First there is no undressing and donning a questionable paper outfit designed, presumably, on the set of Star Trek.  This week, Dr. David Guggenheim aka “The Ocean Doctor” came to visit us at Miami U to tell us about the state of the world’s ocean, its coral reefs, and the other animal life there.  Although the presentations were interesting and visually stunning, the report was not good.  For instance, less than 5% of the coral reefs are expected to remain by 2030 at our current rate of pollution, destruction, and oceanic warming.  Coral supports an estimated 25% of the ocean’s diversity and they are some of the oldest living species on the planet at 4000 years. 

Of all the risks to corals and to oceans, the one that disturbs me the most, and which also seems the easiest fix, is the high environmental cost of fishing.  Watching some of the footage of oceanic habitat destroyed by trawling and the inevitable consequence of by-catch in the fishing industry, I wondered if it was ethical to eat fish at all in this world with 7 billion hungry humans.  On principle, it seems conceivable that we should be able to eat fish raised or caught in a sustainable way.  And aquaculture could potentially alleviate some of the environmental and ethical concerns.  (Whole Foods apparently has good labeling on their fish.)   However, unless you go out and catch your own fish for dinner from a stream or lake, you do not have good assurance that this fish was collected in a way that takes into account sustainability and humane practices.  (Of course, fishing with rod and reel also drives stocking fish into rivers and lakes, which is environmentally problematic in its own way. Dinner has become rather complicated.)  Until we have better practices that do not result in significant by-catch and environmental degradation, the most environmentally responsible decision may be to stick with your greens and beans and let the oceanic habitats recover.  The Ocean Doctor did not discourage eating fish, but like a visit with my regular doctor, I left my meeting with him with the feeling that I needed to reevaluate some of my choices.  

Giant Puff Balls

Giant Puffballs are on the loose in Ohio right now.  I was walking through the woods and thought someone had dropped a load full of cantaloupe.  I love cantaloupe, so I investigated and found instead this giant, edible mushroom.  You do not seem to be ooo-ing or aaaawww-ing.  Let me see if I can get you a closer look.

Now then--aren't you impressed?!  They were bigger than my head, which is apparently quite large if the "large" hats (that do not fit) that I've been crocheting are any indicator.  Giant puffballs are edible before the spores form, so you can cook them up for dinner.  Puffball pizza might be just the thing.  


Just wanted to share the excitement from the Ohio woods.  

Somewhere, Hardy-Weinberg (or Great Songs for Science)

 

I was listening to a few songs by They Might Be Giants about science, which are not bad.  We used to listen to They Might Be Giants while driving to math meets in high school, so it’s good to see that they joined the nerd club formally and are writing songs for the youth about science.  My favorite song that I’ve found is My Brother the Ape, which encourages us to think about all of life as a relation, which the data suggest is accurate.  (However, I’m not sure my actual brother with whom I share 50% of my genome would be thrilled to hear me singing this song, since he’s kind of hairy.) It’s a good song, but you know, not as detailed as you might hope for your introductory biology class. 

 

I recently wrote some lyrics for my intro class when we discussed the Hardy-Weinberg Principle, one of the central ideas in population genetics that helps us understand if a population is experiencing microevolutionary processes.  It allows you to predict the frequency of alleles and genotypes in a population when it meets a set of assumption, assumptions that fit very nicely to music of Somewhere Over the Rainbow, a song that today’s students and their aged professors still seem to have in common.  (Through a series of trial and error, I have learned that they do not know This Land is Your Land or Blowin’ in the Wind, which you may also find shocking and horrifying.)  I have been singing Somewhere, Hardy-Weinberg, and maybe you should too.  (But don’t sing anything in parentheses below!)  It won’t offend your brother (the ape, or otherwise). 

Somewhere Hardy-Weinberg

(Somewhere Over the Rainbow)

Somewhere there’s a population, of infinite size

(Somewhere over the rainbow, way up high)

With random maters and no mutation, selection, or migration.

(There’s a land that I heard of once in a lullaby.)

Somewhere the probability that two alleles will meet

(Somewhere over the rainbow, skies are blue.)

Will be a product of their free-ee-ee-quencies.

(And the dreams that you dare to dream really do come true.)

The likelihood of Big-A Big-A (AA) is going to be p times p,

(Someday I’ll wish upon a star and wake up where the clouds are far)

Or p-squared!

(behind me!)

And little-a with little-a (aa) will be the frequency of q times q

(Where troubles melt like lemon drops away above the chimney tops that’s where)

Or q-squared!

(you’ll find me.)

Somewhere there’s a population of infinite size. 

(Somewhere over the rainbow bluebirds fly.)

Alleles meet in random order

(Birds fly over the rainbow)

In Hardy-Weinberg Equilibrium.

(Why then oh why can’t I?)

And don’t forget the heterozygotes (Aa), they’re out there too

(If happy little bluebirds fly beyond the rainbow)

it’s p times q times two! 

(why then oh why can’t I?)

Flowering Bugs

As much as we like to control nature with our planning and our plows, we still seem to recreate it in our own backyards.  And I am no different, as I have been turning my yard back to a bit of weeds.  I have let an area of Queen Anne’s Lace go to it, which I may regret next year since one spontaneous plant in 2010 seemed to seed an area with a diameter of ten feet or so for 2011; I have a weakness for that plant, so soon it may fill the yard.  I have also planted some sensible natives, like butterfly weed, which is a member of the milkweed family with a shocking orange flower that would inspire a grandmother’s bonnet.  Robert Frost has a poem, “The Tuft of Flowers,” about finding one of these plants after a field had been mowed down by following the flight of a butterfly— Frost imagines the mower leaving this “leaping tongue of bloom the scythe had spared” from “sheer morning gladness at the brim.” Sounds like the stuff of poetry, doesn’t it?   I was expecting the plant to attract butterflies (since the scythe is seldom wielded at my house), which it did.  But tonight I found the plant has also attracted bugs an orange as vibrant as the flower once was.  Imagine Frosts gladness had he found the butterfly weed covered in cool bugs!

After a little googling, it looks like these orange busybodies are large milkweed bugs that breed and feed on the plant and tufted seeds.  Many milkweeds have chemicals that protect them from herbivory, but this bug like the catepillars of queen and monarch butterflies that also feed upon it, can utilize the chemicals for their own protection.  Their bright coloration is like wearing a bright orange vest to advertise your presence—predators see them and leave them alone because they are toxic.  Such a nice surprise to find when I thought the flowering was complete.  My little girl agreed.  It’s a new adventure every day, even if you don’t wander out of the yard.