Saturday, October 20, 2012

Insect


This image is pretty zoomed in from the original so it's not the best quality but this shot actually came out reasonably well.  I know it's an insect...but that's it.

Saturday, October 6, 2012

Hericium americanum



I found this specimen during my last trip to the White Mountains in NH.  This species has several common names including the pom-pom mushroom, lion's mane mushroom, bear's head mushroom, monkey head mushroom and icicle mushroom.  Perhaps many more.  This is a great refresher on why we need binomial scientific names.

Apparently this species and the rest of its genus are edible and commonly eaten in Asia, especially China and Japan.  As with any mushroom you need to be 100% certain you are collecting the correct species.  With many species of fungus there are species that look similar or almost identical that are toxic.  Recipes suggest this mushroom as a replacement for rice in soups but that it is best fresh.  It seems it is very easily cultivated, however.  

Generally grows on decomposing logs, as pictured above.

Sources:




Friday, September 21, 2012

Tarn



I'm still here!  OK so I've been insanely busy for the last few months with work and planning my wedding but now that I'm all married hopefully I can get back to posting.  I know...I say things...anyway, this time the post is about...GEOLOGY!

I'm not very good at geology so I invite you to berate me for inaccuracies in the comments.  The image above I made during my last trip to the White Mountains in New Hampshire.  This is a body of water called a tarn near Mt. Lafayette.  A tarn is essentially a mountain lake.  The basin of the lake is formed by a glacier and is always found on one side of a mountain slope.  You can see said slope above the tarn in this image.  

Often a terminal moraine provides a dam that keeps water in the basin.  What's a terminal moraine you ask? Well that's one bit of geology I actually am fairly confident I understand.  So when a glacier slides across the landscape (glaciers are so huge, by the way and I've never actually seen one in real life...I have to imagine an ice sheet of this size) it picks up a lot detritus including rocks and boulders.  Here in New England if you've ever spied a huge boulder just sitting all by its lonesome in a field with no other boulders around you can be pretty sure a glacier dropped it there.  So anyway, the glacier will pick up rocks and boulders and also drop them.  A moraine is a collection of detritus, soil, rocks, boulders, etc., dropped by a glacier.  A terminal moraine is a moraine formed at the furthest advancing edge of the glacier.  Usually the largest accumulation of debris is at the "snout" of the glacier (the advancing face/edge) and as the glacier finally stops and begins to melt it leaves a (sometimes) massive pile of rocks and such.  

So it's this kind of moraine that provides the dam for a tarn.  Now you can impress your friends by telling them about tarns and moraines.  Fun geology words!

OK I have a few other photos from the Whites I'm hoping to post.  Get ready for FUNGUS!

Friday, June 22, 2012

Farmer Ants

So this is why I love ecology.  Just looking at one organism at a time is often super interesting stuff...I mean have you seen a horseshoe crab???  But often the combinations of organisms that have evolved side by side over millions of years is just downright mind-boggling.

I already was a big fan of ants.  I always find it really interesting to watch them and think about how much of their sensory world involves chemicals, many of which are produced by other members of their species.  Ants leave chemical footprints and generally have a few different chemicals that can mean different things.  Their antennae are incredibly acute chemical sensors, able to pick up very small amounts of molecule.

I also knew that ants sometimes farm aphids but after shooting this process the other day I found that these two facts are connected.  I was unable to access the original article here from science daily but I managed to find a quotation of it here.

Scientists have just recently learned that ants that farm aphids, like the ones below, use a chemical produced by their legs to sedate the aphids they are farming.  Ants will often bite the wings off aphids to keep them from flying away and now we know they're also drugging them.  This seems cruel, from a human perspective, but keep in mind that the generally much larger and more capable ants are also defending the aphids from dangerous predators like ladybugs and other beetles.  It's actually rather like our relationship with livestock.  We mess with their genes and keep them corralled but we also protect them from wolves and mountain lions.

These ant colonies keep aphids because aphids produce a sweet liquid known as honeydew as waste when they feed on certain plants.  And the ants...well they consume the aphid waste.  Yum!

The methodology used to discover this is elegantly simple and ingenious.  They had ants walk on a surface and then placed aphids on both a surface that had and had not been walked on by the ants and watched and recorded speeds and such.  They found that surfaces that had been walked on by ants caused the aphids to slow down markedly.  Especially interesting was when they used a dead leaf as a surface.  Aphids should avoid dead leaves at all costs, it's going to make you more obvious to predators and there's no food there for you.  But when they had dead leaves walked on by ants the aphids kind of moseyed off.  Really cool science, I think.

Oh and here are the images.  The little gray blobs are aphids...easier to see in the web album.





Saturday, June 16, 2012

Two Images of Beetles



Because I'm busy and kinda lazy but I took these decent shots today.  I've got some other new images but I also need to research and write for them so...beetles.  Enjoy.

Friday, June 1, 2012

Convergence and Confusion

I went to the Stone Zoo yesterday and had a great time checking out some interesting animals.  They have a really nice collection, skipping a lot of the usual more showy African animals but including a few black bears, a lynx and a set of Tibetan steppe animals and South American animals.  They generally seemed healthy and active which is always good to see.  The highlight of the day, by far, was their bird show.  Mostly the birds were raptors including a very nice looking bald eagle that I was able to get very close to at the end of the show.  Which...y'know is really cool to see such a big bird that close.

But maybe the coolest bird was their red-legged seriema.  This unusual bird hardly ever flies but rather runs or walks and has a very interesting hunting behavior.  They will grab small animals, usually reptiles, by the tail and then smash them into the ground.  You can find an image of this here.  I wanted to learn a little more about this bird, and couldn't quite remember the name after getting home from the zoo so I consulted a large bird book I've got.  I immediately assumed it was a crane relative due to its long legs and found it there with the other cranes.  Apparently I have an eye for sorting birds into families.

Except really I don't.  This is the really interesting thing about living in a time that we have access to molecular data in regards to phylogeny.  For hundreds, really thousands, of years scientists and natural historians have been sorting animals based on how they look.  It makes sense, of course, that animals that look very similar should be closely related.  And much of the time this is correct.  All insects with a set of wings and a set of hard, protective wing coverings are all coleoptera, everything with a soft, shell-secreting body is a mollusk.  However we forget that birds are tiny subgroup of an already small subphylum and so when you get that specific weird things begin to happen.

Over the course of talking about several of the animals we saw I found myself examining a mammal and bird phylogeny really closely.  I'll talk about the bird phylogeny but you can check out the mammal one here.  So a few things to notice on the bird phylogeny here.  (If you're not familiar with how to read cladograms, basically each fork represents a common ancestor and the lengths of the lines represent time so the longer the line, the longer that group has existed and the closer one group is to the fork of another, the more closely they are related).  So first find the seriemas.  They are actually not cranes at all.  They are what we call a sister group (i.e. the group on the other side of a fork) with a group containing parrots, falcons and the group called passerines, which are all perching birds (basically all yard birds...mainly small birds with gripping, perching feet).  Something else to point out here, falcons are not the same thing as hawks or owls, each of these three bird families are spread fairly far out on the tree.  The falcons being placed with parrots and passerines is something very new, I found an article from Tetrapod Zoology written just last month describing the new molecular data and the reorganization of the clades.

The fact that falcons look just like small hawks and owls really resemble hawks, at least in terms of beak shape and talon shape, is what we call "convergence."  When organisms fall into a similar niche in the ecology (i.e. they are getting their food and living their lives in similar ways) more often than not then evolve to look very similar.  It makes sense.  If you have two families of birds that are hunting other vertebrates they are both going to want to be fast and they are going to want to have very sharp beaks and talons.  And that's exactly what you find.  Even though hawks and falcons are NOT sister groups they look the same because they have both evolved to utilize other vertebrates as energy sources.

So I've rambled pretty long about phylogeny here (it's probably my most nerdy passion) but a few more really interesting things to point out on the bird tree.  Herons, storks and cranes...all different things.  More convergence.  And the most surprising thing (to me)?  Find loons, grebes, and ducks.  All different things.  A grebe's most close relative is a flamingo!  Ducks are also found all the way across the phylogeny from most other shore birds, found in blue.  They are actually most closely related to things like pheasants and quails.

One final note.  I'm now a huge fan of the seriema.  I think they're really cool, very dinosaur-like birds.  One thing I found in my research: scientists now believe their closest relatives where the terror birds.  Which, if you're not familiar with, you should be.  You can start here.

OK, I'm finally done ranting about convergence.  Enjoy learning about terror birds!

Saturday, May 12, 2012

Branta bernicla


Most of us are familiar with the ubiquitous Canada goose but this is another species we find in New England for at least part of the year.  The Brant's (or Brent) goose is, like most New England avian reptiles, migratory between the Arctic where it summers and breeds and the North American coast.  During its stay here it inhabits inter-tidal regions of either sandy shore or marsh flats.  This bird is not entirely marine, however, and spends its summers in the tundra or on grassy islands where its diet consists primarily of lichen and terrestrial plants.

The Brant's goose is primarily herbivorous but will take some animal food as well especially eggs but also worms, snails and amphipods.  (What are amphipods?  The next time you're at the beach find the wrack-line, the line of seaweeds and marine detritus left at the high-tide line, and turn some of it over.  You'll likely see little pale crustaceans start crawling and flipping themselves around.  Those are amphipods.)  Because breeding takes place near freshwater the young Brant's also will feed on insects and aquatic inverts.

There are several subspecies with varying color patterns across the range of the Brant's goose.  As a species it is considered an IUCN species of least concern.

As usual, I reference eol.org.

Sunday, April 29, 2012

Vulpes vulpes

I've been marveling lately on an illustration I saw recently of an extinct species of crocodile lunging out of the water, reaching to grab a Tyrannosaurus Rex.  The event itself, that it occurred on the planet we now inhabit, is a marvel in itself but what I've really been marveling at is the sheer amount of energy involved in that event and how systems involving that much energy all begin their story in the form of single cells (both evolutionary and developmentally speaking).   From just two little cells comes a massive, 30 or 40 foot crocodile death-rolling a T. Rex.  Just so cool.

The day I took the photos below I witnessed what may have been the most wild biological energy I've seen.  The event was too far away from me so I don't have any photographs but here's what I saw: at first we noticed a group of gannets plunge diving.  You can see the group of birds circling around, looking a bit like gulls and then one will just drop out of the air and slash into the surface.  One after another was diving over and over.  That's already a lot of energy but you have to imagine the enormous school of fish that was hidden below the surface as well.

After a few minutes we walked a little further and noticed a second and third large group of gannets plunge diving.  Now I had the thought..."there's an awful lot of fish under there.  I wonder if there are whales nearby."  Sure enough, we waited and began to saw fin slapping, a behavior humpbacks and some other whales will do to signal good fishing spots to their kin.  You see the huge pectoral fin (humpbacks, even though not the largest whales, have the longest pectoral fins) rise up from the surface and then come crashing down, making a noise loud enough to hear from shore.

After watching all this energy, all these cells consume one another for a while we then noticed that there were more cells around.  I did get photographs of these and so they're the title of the post.  Here is Vulpes vulpes, the red fox:




By being quiet we were able to watch these two cubs rough and tumble play for a good 10-20 minutes.  It was really quite cool and a fairly unique experience for me. I've seen foxes in the wild before but never out in total daylight playing like this.

So V. vulpes here is the world's most widely distributed wild carnivore.  And though they mainly feed on small rodents like mice and voles they will eat just about anything they can get: other mammals, small birds, inverts like beetles and worms, decaying fruit and bits from compost piles are all on the menu.  I've even seen foxes "fishing" (for what I'm not entirely sure).

Unlike wolves foxes do not form packs but do live in smaller social groups usually consisting of a mated pair and a few of their daughters who will help to raise subsequent pups.  Like all canids and most mammals they mark their territory with urine.

V. vulpes's territory is limited by C. lupis (the grey wolf) and C. latrans (the coyote) however reduction of the former's range has increased the range of v. vulpes.  The red fox is also capable of inhabiting nearly any temperate terrestrial biome from coastal scrub/dunes (as pictured above) to alpine ridges.

V. vulpes also includes a vast number of subspecies/subpopulations that vary in coloration.  If you see a fox in the United States that is NOT the typical reddish orange of the animals depicted above it is still, in all likelihood a red fox.  Though this exchange did not involve as much energy as a T. Rex or a whale I was still glad I had the opportunity to photograph these beautiful animals and looked forward to sharing them here.  I have a few more that I may just post to the web album.  Enjoy!

One note:  I have been failing to include references for the last few posts on L. littorea and Uca genus crabs. Those along with this post have nearly entirely been based on information from eol.org.  As always this is my go-to reference.  The post on L. littorea also came from my knowledge as a marine educator....yeah, I talk about snails a lot.

Natural History Reading: Four Fish

So as I mentioned recently in my post about dolphin strandings I am finally beginning to see myself as not just a science educator but also a marine educator.  I've worked for a public aquarium for a little over two years now but until very recently I still strictly referred to myself as a "science educator."  The distinction is that my background is in neuroscience and my teeth cutting experience in the field of informal ed. happened a children's museum where I mostly designed experiences related to they physical sciences and my main interests related to animals are still evolution, classification and  the more nerdy, "sciency" topics rather than what I would consider "marine" topics.  However working at a public aquarium for two years can influence your thoughts and perspective and teaching and even though I still hold the belief that the most important way we as educators encourage stewardship, especially with young children, is by scaffolding appreciation and excitement about nature, I am coming to include the "marine" part of my work more and more into my self identity.

So why is this important?  Why the preamble?  Because the book I'm reading right now, Four Fish by Paul Greenberg, I think does a great job of showing how much fascinating natural history there is behind a modern marine stewardship problem like over-fishing.  The book is ostensibly about our (our meaning humanity) relationship with four fish, (hence the title) salmon, bass, cod and tuna.  It tells the historical story of their fisheries and why these four fish have become modern staples.  It deals with the idea of fishing being the last "wild" resource that humans consume and where we seem to be going and where, perhaps, we ought to be going (baramundi farming, spoiler alert!).

But the most interesting part of the book, for me, is the natural history (I know, huge surprise).  Greenberg writes eloquently on how the natural histories and life histories of these particular animals forged our relationships with them and are often counter to how we attempt to continue our modern relationships.  He also relates this concept to fishes he believes are indeed more suited to our continued consumption.

Overall this book is a great read and one of the reasons I'm enjoying it so thoroughly is that I see his writing as a bit of professional development, helping me remember that because I'm a marine educator I don't need to stop being a science educator.  His ability to present current policy and environmental issues through their natural history is quite inspiring and completely enjoyable.  If you eat fish, keep aquaria, love fishing or have any strong emotional ties with fish (read: if you are from New England) I highly recommend this book.

Saturday, April 28, 2012

Littorina littorea


This is an animal that I spend a lot of time with.  The common periwinkle or little winkle (they have big winkles in Europe) is an introduced species that has become ubiquitous in nearly every Northeast US coastal habitat.  Even though this snail is not native I tend to use the terms "introduced" or "non-native" rather than "invasive" when describing this species.  Terminology related to human introduction can be controversial and I find it varies widely between environmental educators and conservationists.  The reason I choose to describe the periwinkle L. littorea as non-native and not invasive is that it is now a part of the ecology.  It's done whatever damage it's going to do and is now a major presence in the New England inter-tidal. The idea of controlling it or removing it is a joke.  Just go to any inter-tidal in New England, but especially a rocky inter-tidal, a  place like Brant Rock in Marshfield, and you will quickly come to see why I know the l. littorea is here to stay.  This idea of shrugging our shoulders and sort of giving in to invasives is, as I say, a controversial one.  I don't want to dwell on the nuances of the conversation here but if you're interested I recommend the book Out of Eden by Alan Burdick.

That being said, some scientists have put forth the idea that it was the very introduction of L. littorea probably in the mid 19th century that transformed much of the New England coast from marsh flats to rocky inter-tidal.  Perwinkles are voracious grazers and preferentially consume the algae and detritus that hold marsh substrate together.  All snails use a structure called a radula to scrape their food from surfaces (check out this video from youtube) and as these snails became more and more numerous they began scraping the rocks clean.

So besides the unfortunate status of this animal as a once invader I LOVE this snail.  They are one of the world's best observation animals because they are hardy, small, easy to transport and if left unmolested will begin moving around a tank pretty quickly.  They do have the slightly unfortunate requirement of salt water but unlike other inter-tidal inverts they are fairly indifferent to temperature changes.  If you live near the coast in the northeast I highly recommend trying these out with students.

Friday, April 27, 2012

Uca


There are over 100 species in the genus Uca, commonly known as fiddler crabs.  I believe, from distribution information, that this is probably uca pugnax, but I'm not certain.  I can't quite seem to find a perfect match to ID this little guy.

Many are familiar with this semi-terrestrial crab as it inhabits sandy beaches and marsh flats of the northeast United States.  These crabs are a great example of what we call "sexual dimorphism."  This is where the male and female of the species look different, sometimes drastically so.  (Cardinals, and many other yardbirds, are another clear example of this).  Di = 2 and morph = form so dimorphism = 2 forms.  You sometimes see reference to polymorphism as well (poly = many) when species have more than two morphs.

In this case the dimporphism is the male's much larger claw.  This is a mate recognition/mate choice feature.  The male crab will wave his large claw, visually and often auditorily signalling to females and other males.  They will also use the large claws in combat with one another.  These little crabs live in pretty close quarters, making small burrows in mud or sand so presumably their lives are consumed by waving and fighting.

Oh, and feeding!  Something I did not know is that their common name comes from their appearance specifically during feeding.  They will use their smaller claw to pick up detritus and move it to their mouths so in the males it appears that they are bowing (with their small claw) a fiddle (their large claw).  I guess I always just assumed it was just an analogy between the large claw and a fiddle.

The day I took this photograph we found a great number of fiddler crabs under the wrack in a marsh flat so the next time you're at the coast poke around a bit and see if you can find these common arthropods.

Saturday, April 14, 2012

Dolphin Strandings

Because I am not just a science educator but also a marine educator I get asked about the recent dolphin strandings a lot. In fact I get asked about whale beachings/dolphin strandings a lot in general. This late winter/early spring they have been in the news a lot so I've talked to more people recently. The question is either "are you helping out?" or "why is this happening?" The former seems to be a kind of vague assertion that there must be something we can do, which really there isn't. The main thing humans do after these large stranding events is perform necropsies. Which relates to that second question. The answer there is we still have no idea. We have some pretty good guesses and there are really smart people working on it but no one knows why whales beach and dolphins strand 100% of the time.

A few things to keep in mind if you're ever asked: this is a normal, seasonal event. Pretty much every year we see this happen. It's happening in larger numbers this year but a lot of our science points to that being, overall, a good thing. We think it's just that there's more dolphins. More dolphins, more strandings. It's received extra coverage this year purely due to numbers.

Second, the dolphins are not sick or going insane or involved in any kind of kool-aide dolphin cults. Here's what we think might be happening: groups of dolphins are foraging in tidal flats, often flats that they have not explored very well. These areas can be very close to sea level and at low tide you can often walk three or four miles further to the sea than you can at high tide. If a group of dolphins is foraging here and suddenly the tide shifts currents can be incredibly strong and the tide can empty quickly, leaving groups of dolphins stranded. Yes, they are very intelligent but they make mistakes.

On my trip to Cape Cod I actually saw evidence of these strandings. I took a few photographs and uploaded them to the web album. I didn't want to insert them in the post because...looking at images of dead dolphins can be upsetting for some people.

At first I was surprised that they had just been left in the marsh. One of these animals was just right next to a trailhead. After thinking about it a bit I thought, well this is part of the ecology, there's a huge amount of energy here. When I talked to one of my colleagues about it, though, she seemed to indicate that really it had nothing to do with that and it's simply that IFAW is overwhelmed. They would ordinarily take them all and do necropsies on as many as possible. Because we're seeing such a large number this year some of them have been left behind.

I think the emotions these animals bring out of people are good in a way. We should care about animals. But I also think there are other animals that could benefit from human intervention more. People believe that dolphins are inherently good somehow or friendly or have some kind of connection with people. It's just not the case. They're large, carnivorous marine mammals. They are very intelligent and have been known to help people but I believe we should try to take a step back and interact with them in the same way we interact with any wild animal.




Friday, April 13, 2012

Storytelling Redux

This came across my email last week. Interesting in light of my post on the same topic:

The Horseshoe Crab Diaries Part Six: In Which Paul Shows a Nice Photograph and Explains Molting

Go to the web album for the full effect

So several things. We went to Cape Cod this last weekend and found evidence of everyone's favorite chelicerate: limulus polyphemus! I thought this photograph was actually one of my best in a while. Even after owning my camera for about six years I'm still learning things about it. I was playing with the various white-balance mechanisms and found that you can have the camera measure the light and tweak the white-balance. Seems really obvious but I just never bumped into the option before. That provided me with a couple of fairly nice shots and this one which I think is well above average.

So I hear this a lot: "I went to Cape Cod/the beach/the marsh/Duxbury/etc. etc. and I saw a dead horseshoe crab/my brother picked up a dead horseshoe crab/it was crawling with dead ones etc. etc." But 99 times out of 100 it's not a dead animal. It's usually what is called a molt. Limulus, like all members of the phylum arthropoda, must remove its exoskeleton periodically. It can be a slow, difficult process because every last inch of its body is covered with the chitinous armor including eyes and its little legs. This is why the molts are often mistaken for dead animals: it looks just like a complete limulus.

Not a dead limulus!

The reason why is that tough armor, great for keeping them safe from predators, is rigid and cannot grow. Instead of growing gradually like most vertebrates they grow in spurts. When they're ready to get a little bigger first they stop taking in water, dehydrating and shrinking the soft parts of their body within the exoskeleton. They then start a crack right along the front ridge of their "helmet" and slowly wriggle their way out of the old armor. The outside of their body is soft at this point but ready to become hard and chitinous again. The arthropod will then grow, usually a full 30% of their current body size, and then the outer layer of their body begins to harden again. The whole process can take a few weeks so arthropods that grow in this way are especially vulnerable to predation during this time. Limulus, lobsters, crabs all seek extra shelter and typically focus entirely on staying safe rather than feeding or any other behaviors during this time.

Many people have eaten soft-shell crab or lobster. These are not different species but crabs and lobsters that have been trapped just after molting. By designing a trap to look like a comfy, safe cave fishers are able to trick the arthropods into crawling right inside. Instead of safety they walk right into the waiting clutches of hungry terrestrial vertebrates.

The next time you're walking around on the mud flats keep an eye out for these signs of limulus.

Housekeeping

Just a few things possibly of note to any Mycelial Network readers out there in TV land. First, I totally missed the second birthday of the Network. Yay! You're two now, Mycelial Network! What wonders will you unleash on your adoring public in your third year of life?? No one knows!!

And I've recently gotten myself full-time employed like a real person. This means I'll be a little busier (though it's not like I've been writing up a storm anyhow) but I'm going to continue to try to make a point of posting on my weekends especially during spring and summer when I'm out in nature the most and I'm taking the most photographs. Speaking of being out and nature and taking photographs, stay tuned for a couple of posts today and tomorrow.

Wednesday, April 4, 2012

90 Trillion Cells

"So if you were to take all the bacteria in your body and just made them into one lump it would be about three pounds."

"Think of it as another organ, I mean, your brain's about three pounds..."

-Carl Zimmer on Radiolab

Monday, March 12, 2012

The Horseshoe Crab Diaries Part Five: In Which Paul Has a Genuine Self-Directed Learning Experience

Last week I was reminded of why I do the work I do. Of course I have a lot of reasons why I do what I do: I love working with live animals, I love museum people, I love getting paid to take students to salt marshes and our other beautiful coastal New England habitats...

But the real crux of why I do what I do and not some other kind of education is that I really believe that self-directed learning experiences are the most influential on future behavior. The data back me up on this (I don't have a citation for you here, I just remember reading a lot about this in graduate school...I'd be happy to try to dig one up if anyone's interested). I had two separate experiences that reminded me how motivating (how much dopamine is involved) these experiences can be.

Last week I was teaching a class on classification (i.e. how scientists group animals and decide how they are related). We wanted to represent the eight major animal phyla but the phylum platyhelminthes (flat worms) are tough to fine. While they are a very specious and common kind of animal many of them are either parasitic or tiny or both.

So there I am, it's towards the end of the last class for the day and I'm looking at the horseshoe crab we brought. Particularly I'm looking at his legs. Horseshoe crabs have these little white boogers on their legs and when I first started my job I never really noticed them. Then I started noticing but I never thought much about them. Then I learned from an aquarist that they are alive; they're animals. So I'm standing there in class and my coworker comes over and sees me looking at them and asks "Oh...are those platyhelminthes?" I wasn't sure...but I thought, maybe they are.

Turns out they are...I immediately looked into it after work that day and found this great article about different animals that "live on limulus." There's a section a ways down about flat worms and describes the current confusion in the literature about whether these flat worms are parasitic or commensal or what. The next time you're at a salt marsh, if you pick up a limulus (carefully by the "helmet") and look at his or her legs you may notice these little white "boogers." If you poke one gently you'll see them start to move and probably notice the front of the animal poking around upwards, away from the body of the limulus. These are probably the only flat worms I've ever really observed.

These experiences (my second one involved learning something pretty specific about the way sea urchin's internal skeletons are set up...probably too technical to add to this post) reminded me of two things: I still have a ton to learn about the animals I work with and these self-directed learning experiences are highly rewarding and the most likely to direct my future knowledge and behavior. Because I went from noticing but not really knowing to noticing and curious to noticing and knowing I am a lot more likely (this claim is based on my personal experience) to remember this and be able to use this information in the future. I really don't think there's any way I can forget that those little white blobby guys are flat worms.

I think the upshot here is: if you are an educator it is your duty to try as hard as humanly possible never to stop being curious. If we are asked a question by our students or we realize that we don't understand something about the subjects we teach about it is imperative that we learn more. I knew this to be true before last week, it is something I have always believed intellectually, that the best educators are life-long learners. I just hadn't had such a rewarding learning experience like this one in a while. Thanks again, limulus!

Sunday, February 19, 2012

Story Telling

I've been thinking a lot about stories recently and how they apply to science education. My feeling is that a lot of science learning at the upper middle school and high school levels focus heavily on memorization of facts. There's always exceptions to these kind of generalizations but I also have the feeling that if we utilize the power of good story telling we may be giving our students more. A compelling story has an intrinsic way of getting into our brains and sticking there. I can't stop thinking about that research I wrote about showing how bacteria could become organelles in an amoeba in only six weeks. There are pretty meaty science facts set in that story but the fact that I first heard it as a story and then told it again as a story changes the learning that's going on. If I had read a journal article describing the outcomes of the research and posted something that just had the facts it would be a very different experience both for me and for those reading the blog. And as a science educator, remember that every piece of knowledge has a story behind it. There is a researcher or explorer that really lived or still lives who found something out about the world, often in surprising or fascinating ways. I think it's important to tell these stories rather than just explain the theories and facts that came out of them. Tell the story of Darwin's voyage on the Beagle, the story of Newton locking himself in his room and writing the Principia, or the story of Arcimedes. These were real people and their stories have a lot to teach about science and humanity.

Thursday, February 16, 2012

Natural History Reading: The Fragile Species

I am almost finished with Lewis Thomas's, The Fragile Species. Frankly, I don't recommend it. I usually flat out love Thomas's writing and if you've never read him I highly suggest The Medusa and the Snail and/or The Lives of the Cell. They are some of my favorite science writing.

In this book Thomas takes up the subject of humanity and, as a medical doctor, spends most of the book opining about the problems of public health. Since it was written a full two decades ago it is rather outdated (even though many of the public issues he writes about are still issues he addresses them from a very different perspective) and I think that has a lot to do with why it falls a bit flat.

However, nearly all the way to the end Thomas describes one of the most interesting lines of research I have ever read about. In the late 1960s some researchers at the University of Buffalo, including one Dr. Jeon, were doing some work on amoebas. They had found a way to transplant the nucleus of one amoeba strain into another. Amoebas are unicellular eukaryotes, the very simplest creatures in the lineage that eventually reached us. This transplanting technique offered up a good deal of insight into genetics.

Tangentially, it would seem, some of Jeon's cultures became infected with bacteria. Rather than just destroy the cultures and start fresh, Jeon fought to keep his precious experimental organisms alive and healthy. He succeeded in getting them back to apparent health; the amoebas returned to reproducing at their normal rate, indicating they were healthy. However each still contained a load of about 50,000 bacteria.

Jeon began some experiments to get rid of the bacteria entirely. He found whenever he was able to destroy the bacteria, such as by exposing them to a heat they could not tolerate but the amoebas could, the amoebas promptly died. Quickly Jeon discovered that they amoebas and the bacteria had become symbiotic. Perhaps more accurately, the bacteria had become organelles; they were now vital to the amoebae.

By thinking long enough about it I felt I had resolved how something like our relationship with mitochondria could have evolved but this experiment shows that it can happen in a remarkably short amount of time. By continuing this line of work the researchers found that it could happen in as little as six weeks. Six weeks! To potentially develop an entirely new kind of living thing. Potentially an entirely new kingdom could develop out of this kind of event. This is, in fact, probably how eukaryotes first arose from prokaryotic ancestors. One bacteria infected another bacteria and then they simply became organelles.

Weird but true science. I feel like a description of this experiment should find itself somewhere into any introductory biology course whether at the high school or college level. This is just remarkably cool stuff.

Phylogeny



This image made me laugh out loud. It accuarately represents the phylogeny but the fact that the chosen representative for the echinoderms' sister group, the chordates, is homo sapiens, is pretty silly. We are very derived chordates. If you laughed out loud on first site, you too might be a huge nerd.


Wednesday, February 15, 2012

Misinformation

This article, published on the National Geographic website, came across my radar today:


I hesitated to even post it because this, frankly, is just bad reporting. I'm ashamed at the National Geographic for allowing it on their website. Here's why it's not journalism:

The title of the article claims "Shark-Attack Deaths" are "Highest in 19 Years." What the article fails to mention, and what the "journalist" who wrote the article probably didn't even bother to research, is that 2011 shark attack deaths went from the average of 5-7 to 12.

So there's one way to say that. You could say it doubled. O my! The sharks are out to get us! But then, if you take a deep breathe and remember how to do actual statistics you might remember that when you compare the numbers 7 and 12 to the billions of times human beings go swimming every year this figure becomes literally (and I am really using the word literally) meaningless. There is no statistical significance. Period. It's like comparing the mass of two objects and being short a couple of protons.

So I'm not just hyperbolizing this time: this article is actually not saying anything. So if anyone asks you about the rise in shark attack deaths...now you know...they're just not on the rise.

Saturday, February 11, 2012

Blog

Natural selection has acted on the mycelial network and it has speciated!

To view the mycelial network's sister clade go to http://oneswoop.blogspot.com/.

The blog is called "One Fell Swoop" but the url onefellswoop.blogspot.com was taken by a blog with only one post that has not been updated since 2002. The one post is moronically self indulgent, too, something about getting a haircut. I'm pretty sure it was written by a teenager. Which is not to say teenager's shouldn't write but...I mean just go look at it for yourself.

In any event I ended up with the url oneswoop.blogspot.com. Which is annoying. But there it is. I have no idea who should read this blog. I have no idea what the purpose is. I'm pretty sure it's a blog about "hey, isn't this weird/cool/interesting/crazy/etc."

(Disclaimer: this is not actually how speciation or natural selection work.)

Friday, February 10, 2012

Reblog: Radiolab's Killer Empathy

I seem to have completely lost my ability to write. In the meantime listen to the folks at Radiolab talk about someone who works with giant crickets.


Monday, January 23, 2012

Photo Time



Because I haven't posted a photo in way too long and it's winter and even though it hasn't been that bad we still need to be reminded the green is coming back, here's a photo: it's of moss!



Salt Marsh Snails

I've been meaning to write this post for a while but I hand't managed to figure out what the upshot or the moral of this story was. I think I figured it out so here goes:

Back in the fall I led a trip with some Boston Public teachers and their students to a local salt marsh. I visited the classrooms before and after the trip to support the students' learning and the teachers' goals (and their learning as well).

There are two main types of snails you see in Northeast salt marshes, littorina littorea, the common periwinkle and melampus coffeus, the coffee bean snail. Littorina is marine, it breathes water and spends most of its time under water while melampus is terrestrial, it breathes air and while it lives right on the edges of tidal creeks it is never seen in the water. When the tide moves melampus will react by climbing a stalk of marsh grass to avoid being drowned.

During my trip back to the classroom with one of the teachers I found she had a book about salt marshes and I had a little down time before I met the students so I decided to flip through the book. I found a photograph of what looked like littorina climbing up marsh grass with a description that periwinkles climbed up to avoid drowning. "Hrmm..." I thought. I knew that periwinkles were marine and I had never seen this behavior before. Littorina tends to eat algae and not marsh grass so I thought, "maybe it's feeding, but I doubt it." I talked to the teacher who had used that image during one of her lessons. "I'm really not sure what's going on in that image, but I'll look into it."

So I did and I discovered that it was indeed littorina in the photo, just not littorina littorea. It was another salt marsh snail (in fact common name, salt marsh periwinkle), littorina irrorata. These periwinkles do feed preferentially on marsh grass and not algae and I quickly turned up a number of similar images of littorina irrorata climbing up grass to feed. Apparently this species can be found as far north as Massachusetts but is more common slightly further south so I was not as familiar with this snail.

At first I thought this story was about being careful about what you read, especially when it is written by non-scientists (like me!) and to fact check your sources. But that's an old story and most of us have heard dozens like it. I realized that this story really held a moral for me and not the teacher. I didn't realize this because I instinctively acted on the moral, I did the research, figured out what the image was all about and reported back to let her know what I had found. I didn't just throw up my hands and say "Oh, it's probably just l. littorina doing something weird I've never seen before."

So I think the moral is this: it's most important to make sure you know what you're talking about when you are the specialist. As an ambassador for robust inquiry science education it is even more imperative for me to assume I don't know everything and that when I see something that doesn't fit my preconceptions it is even more important for me to do the research so I can reconcile the new information. So I encourage all of you who are science educators in any respect to always be on guard, especially when you think you know exactly what you're talking about. You may be surprised that you don't...and you might actually learn something.

Thursday, January 12, 2012

More on Alive or Not Alive

Speaking of Carl Zimmer and speaking of things that might be alive, celebrated curiosity monger Carl Zimmer posted this on his blog:


I scrolled down to the comments and immediately got a science headache. Not recommended unless you're actually a taxonomist.

Stay tuned, an actual post has been brewing...

Saturday, January 7, 2012

Natural History Reading: Parasite Rex

I just finished reading Parasite Rex by my hero, Carl Zimmer. The last natural history book I read and wrote about here on the network, the Secret Life of Lobsters I found somewhat lackluster and difficult to get through so this read was a breath of fresh air.

As usual, Zimmer tells the story of his interactions with the scientists who study parasites so eloquently and so intimately that it demands your attention and your affection. He makes the often bizarre and macabre-seeming world of tapeworms, hookworms, flukes and ticks exciting and wonderful.

I don't want to spoil too much of the fantastic science in this book but something Zimmer continues to come back to throughout is how much our still-burgeoning understanding of parasitology has begun to really change our understanding of what we thought were hard and fast ecological concepts. One example he gives has to do with the common notion that part of the ecological services that large predators (such as wolves) provide is to reduce the spread of disease through an ecosystem. Prior thinking goes like this: animals that are sick are easier to catch so predators spend less energy if they target these sick animals as food sources instead of healthy animals. This will benefit the ecology because that sick animal is now out of the ecology, it can no longer spread its disease to other members of its species or possibly other species.

The problem is that parasites (and parasites here are defined as all eukaryotes, so animals plants and fungi, that spend all or part of their life cycle either inside a host or feeding directly from a host) often spend part of their lives in one species and another part of their lives inside another species. Let's say there's a species of worm that infects a moose in one part of its live and a wolf in another. Natural selection will have provided that worm with an ability to modify the moose's behavior such that it is easily caught by wolves. It is in that worm's best evolutionary interest to continue its life cycle. So the wolf isn't reducing the spread of disease at all. It's actually actively taking part in spreading the disease. While the previous thinking still can apply to bacterial and viral infections it may have the exact reverse process with eukaryotic parasites.

He also gives descriptions of how many parasites change the behavior of their initial host so drastically that they make food more available for the predators. There is a particular parasite that infects killifish, a small salt marsh fish, and then herons. The behavior of infected killifish is so drastic that it makes them 30% more likely to be caught. This may not be entirely sound but one way to look at this is that food is 30% more available for the herons therefore the marsh can support a larger population of the birds than it could if this particular parasite did not exist. The parasite isn't exactly increasing the amount of food but it is increasing its availability.

This book really made me rethink some of what I know about ecology in some pretty interesting ways. As I mentioned it is written in Zimmer's usual smooth and easy to read prose. His writing is easily accessible and he is one of the best authors for those who are interested in science but feel intimidated or don't think they have a solid background. Parasite Rex was absolutely a great read.