Sir David Attenborough You Just Made My Day!

Normally when I am working on developing an educational program or an exhibit I keep detailed bibliographies on all my sources, since the end product has to go through some serious critiques. But the one time I slip and find something truly cool I forget to write down the source and then spend the next 13 years trying to find it. 

The whole problem started when I set out to write a plant fact sheet about the Nepenthes gracilis.  This is an extremely large species of carnivorous pitcher plant which lives in tropical jungles of Southeast Asia. Unlike the pitcher plants most of us are used to seeing in swampy areas of North America these pitchers grow to close to twelve inches long and hang from a creeping vine.  Now a pitcher that large has to be catching and digesting something really cool, so to the literature I went.  A researcher went through a forest dumping out pitchers into a pan to inventory what the plant was digesting. In one pitcher he found half of a large dead rat.  Cool plants which can ever so slowly EAT A RAT!!!  What could be cooler than that?  For months I stuck to my guns telling everyone I hadn’t made it up while trying in vain to find the copy of the research paper.  No luck.

Fast forward 13 years and I am watching PBS’ Attenborough's Life Stories and who but Sir David Attenborough himself should say, while taking about Nepenthes gracilis, “they have even been found to be able to digest things as large as a rat.”  I backed up the DVR about three times just to make sure I had heard him right.  So for all you people who had doubted that I was right take it from Sir David Attenborough.

Scientists have discovered even more cool things about the Nepenthes sp. over the years, such as there are more than 150 different species of animals which will live inside the plants pitchers. Also the shape of the pitcher’s cover helps to drop insects into the digestive liquid when it rains.  The underside of the pitcher’s cover is coated in a flaky waxy like substance and when rain hits the top side it causes the insects to lose their grip and fall.  Also scientists have found a whole new species of Nepenthes which appears to be much larger than all the other known species. Also during this trip scientists found a species of Nepenthes which had been thought to be extinct.

Want to know more:

http://www.botany.org/carnivorous_plants/nepenthes.php
http://www.sarracenia.com/faq/faq5400.html
http://www.sccarnivorousplants.com/troppitch.html
http://www.kew.org/plants-fungi/Nepenthes-rajah.htm

Sergei Winogradsky Made Me Want To Puke!

Let me just start out by saying I have TONS of respect for all the cool things Sergei Winogradsky did for science. He was a Russian scientist born in 1856 and is the founder of modern microbiology.  Sergei used a columns, later called the Winogradsky Columns, to watch the interactions of different groups of bacteria over time and under different environmental conditions; lots of hydrogen sulfide gas, lots of nitrogen, extra carbon. He also looked at how bacteria colonies changed over time as organic and inorganic compounds were used up.

You have probably seen a Winogradsky column in some nature center or science museum sitting in a sunlit area unlabeled and probably walked right past it thinking “well that’s weird”. 

 

That is just what happened to me for almost a whole year. I worked at the Museum of Science, in Boston, MA, in the greenhouse exhibit and as I watered the plants would walk past these two large plastic tubes with white caps.  They made great plant stands, but they bugged me. I had seen things just like this on other museums in the United States, France, and Germany with no labels explaining what they were.  So, on a slow day I asked my boss Bob what they were. “Oh, they are old Winogradsky columns.”  he replied. 

Curious I searched books in the library and the internet trying to find out more about them. I found out the different colors, of bacteria, and where they were in the column tell you about the bacteria’s environment; is there oxygen, is there carbon, is there sulfur, and much more. Each type of bacteria was a different color, so it would be easy to look at the colors to pick out sulfur rich areas by looking for the red bacteria. Excited I looked at ours. They were green from top to bottom. Where were all the other colors I wondered?   On Monday I peppered Bob with all my new information and admitted I was confused because ours were all green.  They need to be recharged he explained. Once the bacteria have used up all the sulfur, oxygen, carbon and other compounds all the other bacteria die and you are left with just the green bacteria.  If I wanted to he would help me recharge them only I had to get two dozen eggs from the cafeteria.  Smiling I entered the kitchen explaining to the chef I needed two dozen eggs for a science experiment and with much fear on the chef’s part he handed over the eggs. Bob and I popped off the five foot columns’ lids and started scooping mud into large buckets.  As I was explaining to a group of visitors what we were doing swish, plop, slash right into my mouth lands a huge clump of foul smelling mud. Immediately the gag reflex kicks in as I try to spit out all the mud, but I can still taste it. I run across the second floor as fast as I can trying not to puke to the restroom.  A few minutes of dry heaving and a few gallons of water to rinse out my mouth later I return to the exhibit.  We shred newspaper, crush up eggs and stir it into our mud buckets before dumping it back into the columns topping them off with pond water.   

A few days later we had all sorts of colonies of bacteria red, purplish, rust colored, black, darker green, and white. Pockets of red where there was more egg (sulfur) than other areas. A black layer formed near the bottom where the bacteria which thrive with no oxygen lived. Three shades of green some of which used oxygen, found near the top of the column and the ones that didn’t use oxygen in the middle of the column.   As the months went by the colonies changed the black layer grew as the mud settled and the trapped pockets of air got forced to the surface. Slowly the red disappeared as the eggs were eaten up by the sulfur loving bacteria.

So, if you happen to see a Winogradsky column in a museum look to see what colors you can find and if it is all green nudge then and tell them to recharge their mud for the sake of Sergei.

 

Want to know more:

http://www.personal.psu.edu/faculty/j/e/jel5/biofilms/winogradsky.html

http://www.smccd.edu/accounts/case/envmic/winogradsky.pdf

http://www.woodrow.org/teachers/bi/2000/Winogradsky_Column/winogradsky_column_p2.html

Zombies Do Exist!

I recently saw my MSN scrolling news headlines stating that zombies are not real. Oh come on, does the author of that article know nothing. Zombies do exist they just aren’t the decomposing, foul smelling, brain eating former humans that we all know and love from the movies. They are hornworm caterpillars, aphids, sawfly larvae and many more insects!  

My two favorite insects, the Ichneumonid and Braconid wasps, are responsible for many the zombies running around.   If you have ever been fortunate to come across the largest Ichneumonid wasp (Megarhyssa atrata) you probably thought to yourself “Holy crikey! What is that!” Female wasps, like the one below, have a huge ovipositor (an organ for laying eggs) which can be up to three inches long!

 

Scientists aren’t quite sure how the female finds her zombie victim, a horntail wasp larva, it maybe through chemical smells given off by the larvae or she may be able to sense its vibrations as it moves under the bark of the tree. Once she has located her victim she sticks her giant ovipositor into the tree piercing the horntail wasp larvae and laying an egg on the larvae.   

The female Braconid wasp is not as cool looking, but anyone who has planted tomatoes in their garden has probably seen some future zombie crawling around.

 

 

Braconid wasps will lay eggs on tomato hornworms, the larval form of the hawk and sphinx moths. You’ll often see big cubby green caterpillars on tomato plants with little white ovals sticking out of their backs, those are the wasp eggs.  

 

Once both wasps eggs hatch they go to work eating their victims alive. The wasp larvae start by eating their victim’s fat deposits then their guts.  If you see one of these zombies crawling around, which they can as long as the wasp larvae has not eaten their nervous system or their heart, you can see the wasp larvae crawling around under the skin of the caterpillar. This rather gross process goes on until the wasp larvae are just about to pupate. Just before the wasp pupates is kills its victim consumes what’s left of the caterpillar’s gooey insides and then chews its way out and creates a cocoon somewhere nearby.   

So yes zombies do exist and they may be living in your backyard!    

 

Want to know more:

http://www.faculty.ucr.edu/~legneref/identify/ichneu.htm

www.youtube.com/watch?v=zVebxrfHfZQ

http://aggie-horticulture.tamu.edu/galveston/beneficials/beneficial-04_braconid_wasp_on_hornworm.htm

http://www.ctahr.hawaii.edu/organic/downloads/Braconid%20Wasps%20FINAL.pdf

Trying to think of things to write on this blog I asked for help from my friend’s son Ben. He wants to know: “Why does a platypus lay eggs?”  Well, here goes nothing and I will try to make this as painless as possible.

The simplest answer to that question is because there were once many egg laying mammals around which have all gone extinct.

Scientists break mammals into three large groups:

Prototherians - which lay eggs (eg. platypuses and echidnas)

Metatherians - young develop in pouches (marsupials such as kangaroos and koalas)

Eutherians – ‘modern mammals’ which give birth to well-developed offspring (rabbits, elephants, horses, and humans, ect.)

All three of these groups of animals share  three of the characteristics which are unique to all mammals; hair, three inner ear bones, and modified sweat glands which produce milk (mammary glands). 

Members of the Prototherians (platypus and spiny anteater) represent a very primitive form of mammals and still have some of the characteristics of their ancestors, for example the ability to lay eggs. If we look at Date-A-Clade, which shows how organisms are grouped together based on common characteristics, we see that the line for the platypus branches off from that of other mammals 166 million years ago.  All of the other primitive mammals below where the platypus and other mammals branch off were egg layers too. All of the egg laying mammals above the split evolved over millions and millions and millions giving us marsupials (kangaroos) and placental mammals (cats, dogs, and humans).

Want to know more about the Protherians check out these pages:
http://www.scientificamerican.com/article.cfm?id=extreme-monotremes
http://www.mammalsrus.com/prototheria/prototheria.html

 

A Sea Cucumber Made Me Do It!

Working as a naturalist/environmental educator one question I get asked a lot is “How did you get into doing this?” Well, the truthful answer is: a sea cucumber made me do it.

Picture if you will a small child sitting on a bunch of rocks in Acadia National Park watching a Park Ranger talk about tide pool animals.  As she talks she hands around a bunch of critters she collected for us to look at. Here comes the sea cucumber in all it slimy fun.  She warned us not to squeeze it too hard, easier said than done for something wet and kinda slimy. Into my five year old hands it is passed, and I squeeze it scared I will drop it.  Suddenly a jet of water spurts out and hits the back of the guy sitting in front of me, and now it feels like a shrinking limp piece of spaghetti. A few second latter and maybe one squeeze too many from me out fly something that looks like guts. Terrified I look at the park ranger where she smiles and tells me it is ok, ‘he’ll just regrow those later.”  WHAT! My little 5 year old mind is thinking how do you regrow your guts? What my five yearold self had just discovered was two ways a sea cucumber will protect itself against attackers.  And thus begain a lifetime of wanting to know if there were other really cool things out there in the wild.

So here is the scoop. Sea cucumbers are an invertebrate which means they have no bony skeleton like you and I. Their “skeleton” is made up of water or as scientists like to call it a hydrostatic skeleton. If you were to pick up a sea cucumber and threaten it, ie sqeeze, it will jet out this water to make itself smaller in size. A great defense against a predator that has just seen its meal shrink in size by almost half.  If you were to keep squeezing, like I did, a few things might happen the grossest being the getting rid of some of their internal organs. Now if you see this happen your first response will be to drop it and run away screaming, which if you were a predator would be a good thing for the sea cucumber which gets to live another day.  Scientist are still discovering how and why sea cucumber can regrow their organs and hope that this might be able to help humans in the future.  One scientist’s research shows that being able to get rid of some organs may help the sea cucumber get rid of parasites living in their guts.

Want to know more? Check out these resources. http://animals.nationalgeographic.com/animals/invertebrates/sea-cucumber/

http://suite101.com/article/amazing-sea-cucumber-facts-a228929
http://www.sheddaquarium.org/seacucumbers.html
http://www.spc.int/DigitalLibrary/Doc/FAME/InfoBull/BDM/17/BDM17_22_Frankboner.pdf