Friday, March 31, 2006

The Circus is in town!

Welcome to the 7th Circus of the Spineless!

We have all manner of posts for you, this month. With this handy dichotomous key, we can help you identify any post you might come across. Be sure to key out your specimen properly, or you might be surprised what "Inverteblogs" will appear.

1a. Post is not about Porifera ........................................ 2
1b. Post is about a sponge:
Circadiana (a.k.a. coturnix) with: sponges have circadian clocks?

2a. Blog is about an arthropod ...................................... 3
2b. Blog deals with a mollusk ........................................ 8
2c. Blog is about an echinoderm:
Medlar Comfits regales us with: Breakers Laundry

3a. Blog deals with Chelicerata ..................................... 4
3b. Blog caontains Lepidoptera ..................................... 5
3c. Blog deals with Diptera ........................................... 6
3c. Blog deals with Coleoptera .......................................7
3d. Blog deals with an insect that looks like another:

Bev provides the audience with: Insect Imposters

4a. Post is about a big spider in New Zealand:
White Tail Spider thanks to Pete
4b. Post is about a smaller spider in the northern hemisphere:
Bev with Spider Ranch

5a. Post is about moths and light pollution:
Rigor Vitae presents a Moth in the night sky
5b. Subject of post looks like a carpet:
Cindy brings us Scaled Wings
5c. Blog has picture of moth just sitting there:
Ben has a picture of A moth hanging upside down.
5d. Moth is in florida:
thingfish23 finds out that Sometimes they come back

6a. Blog discusses halteres:
Budak tells us A tale of two-pteras
6b. Post is about insects eating insects:
Ben has a picture of A light snack?
6c. Perhaps the most disturbing post in the circus:
Thoughts from Kansas forces us to confront Sometheing we don't want to have - ever.

7a. Post gets inspiration from the ancient Egyptians:
Medlar Comfits praises Dung Beetles.

8a. Mollusk has a really funky shell:
Aydin found a Frankensnail.
8b. Mollusk has been attacked, sometimes repeatedly:
Pascal found evidence of Snail predation.
8c. Last but not least:
tai haku has pictures of Colorful Squid

Apologies that this is a little late - I got lots of good posts. Hope you enjoy them as much as I did.

Thursday, March 30, 2006

COTS right here!

I'm extending the deadline for the Circus - Blog Carnival has it listed a little later, so please get things to me ASAP, but if you're a little after 4pm - no biggie!

Monday, March 27, 2006


Submissions for COTS #7 will be due on the 30th at 4pm. Don't be shy - send me a link!

capn.pituitary AT

or, place a comment on one of my COTS threads.

See you here on the 31st!

Wednesday, March 22, 2006

Sinister snails

Dietl and Hendricks (2006) recently published an analysis of left-handed versus right-handed marine gastropods (mostly Conus and Busycon). Seems their results indicate a preference for sinistral shells. I want to get a copy of the article before getting into more detail, but since I went to school with the second author, I thought I'd give a quick shout out.

BBC news post.

Dietl, G.P., Hendricks J.R. 2006. Crab scars reveal survival advantage of left-handed snails. Biology Letters. Early Online Publishing.

Tuesday, March 21, 2006

It's not what you eat: it's the way how you chew it.

Going through my samples that I had collected this past fall, I came across a few examples of predatory attacks on snails:

Vallonia pulchella

The aperture of this Vallonia sp. was peeled back considerably - perhaps about 1/3rd of the entire body whorl. Yet the snail was able to regrow a new aperture (albeit short of the original length). As you'll see later, the regrown shell does look scarred - like a healed burn or deep cut on our skin. There are two points that are most interesting to me here: 1) this snail is less than 2mm wide, and 2) the snail survived an attack from a predator small enough to delicately peel back the shell of this tiny snail (my guess is some kind of carabid beetle).

Neohelix albilabris

At least, I assume it's a Neohelix. It's about 3cm wide and fits with descriptions that I've looked up. Aydin - if you have a better ID, I'm all ears. What really amazes me about this snail is the fact that it survived at least two different attempts to peel away the shell (black arrows).

Pupoides albilabris

The "White-lipped Dagger Snail" (cool name) has only been reported for the area where I found it once (Theler, 1997). However, the hill prairies of southwestern Wisconsin are under reported and surveyed, so I'm not surprised. What impresses me about these sampes is that there is a predator dextrous enough to peel back the body whorl to get the snail inside. I know that some birds and shrews eat land snails, but to peel back a shell at this level of detail probably requires something smaller. Something in the Caribidae, perhaps (ground beetles).

This relates to a post by Aydin: about snail predation as regards snail survival. As biologists (paleobiologists) we often see the remains of what doesn't work. Given the mathematical nature of the intrinsic rate of increase, it does not take much change in this rate to result in a significant improvement in reproductive success.

There are many changes in shell morphology that have been assumed to convey some improvement in success for terrestrial gastropods. Most of these have to do with the thickening of the aperture or "teeth" inside the aperture. However, my thought is, that the most successful adaptation for snails to survive predation is the mantle's ability to reprecipitate calcium carbonate.

Thursday, March 16, 2006

Birds and Cats

My wife and I have two cats. One, Birke, is a textbook mouser. He plays with toy mice every day, sometimes for nearly 15 minutes at a time. When he was younger, I literally watched him play with a single mouse-toy for more than an hour. Like I said, he likes mice.

Our other cat, Pippin, loves to chase bits of paper across the floor, but has shown a real affinity for birds. He's a tad pudgy and doesn't jump as high as he used to, but little winged things really get his attention (he loves the bugs that get into our house as well). Earlier this week, we had a Pine Siskin pigging out at our window feeder - and Pippin was right there:

We keep our cats indoors, but let them outside with a leash and supervision - cats are far too good at catching wildlife to let them out on their own. But apparently, this Siskin didn't care - the cat swatted the glass several times, and the bird just stayed there, eating sunflower seeds. I can feel winter loosening its grip - both on my wife and I, our cats, and the birds. It will be nice to have summer birds at the feeders again. Besides, it will give Pippin something more to watch...

contact me

PS - you can get hold of me either through email (capn.pituitary AT or by leaving a comment on this post, or any other recent entry.

I've got three super-punctual folks who have sent me entries - be sure to get yours in by the 30th!

Wednesday, March 15, 2006

Squish-crunch vs. Crunch-squish

As a paleontologist, I'm faced with the fact that all of the stuff I work with is whatever didn't decay and rot away. I worked for several years at the UW-Madison Geology Museum both as project assistant, researcher, and tour guide. Our tours are geared towards kids, and one thing kids love is mild gore. So, as a mneumonic for remembering the difference between vertebrates and invertebrates, we had squish-crunch and crunch-squish. Which is what each group would do if they were stepped on. A bit gruesome, perhaps, but it got the point across. Vertebrates, with their bones inside the body will squish before the skeleton crunches. Invertebrates, with their hard parts on the outside, obviously will do the opposite (if they have anything to go crunch in the first place - but we don't find them as fossils, so that's not as much of a concern in a geology museum).

Those of us involved in paleontology can get lost in our own world. One of the things I like about having to give tours to 4th graders is that one is forced to put complex ideas into simple (perhaps graphic) terms.

COTS right here!

At the end of the month, swing on by for the rootinest, tootinest, spinelessest blog carnival of them all. Circus of the Spineless will be right here. If you have a submission, please send it in by 4pm CST, March 30th. See you here!

The little engine that could (tell you where it's going).

Earlier, Aydin at Snail's Tales posted photo evidence for his interpretation of a locomotive engine. I still think there's a chance it might not be an engine, but the simplest and most complete answer is that they are indeed locomotives.

So what about his first question? How can you tell what direction it's travelling? Trains don't do too well when pushed, so the majority of the time (if the train is moving), it is likely that the locomotive is pulling the cars. The cases where this may not apply are usually in rail yards or along industry spurs. If you see a picture of a long train, out on the mainline you've got a better than 50% chance that it's pulling the cars and not pushing them (assuming, again, that the train is moving).

I hinted at a case where you could be nearly 100% certain of dirction:

The picture at top, the steam engine is moving backwards and forwards below. Notice the smoke plume leaves a nice trail. Provided the wind isn't too strong, you could get an easy idea of motion. However, this doesn't always work either: sometimes they don't make much smoke.

Tuesday, March 14, 2006


Blogger has been acting a little odd. This is the first time I've been able to update in several days.

PS: Circus of the Spineless will be here (and I will have a backup to keep people going just in case)

Monday, March 06, 2006

Where railfanning and science collide

A recent post by Aydin about trains from above piqued my interest. At first, I looked at his interpretation and, being something of a railfan, I felt that I could correct and supplement his interpretation.

At first, I discounted his interpretation of the two darker-roofed cars on the left side. But, trying to be objective, I had second-thoughts. I can't just discount his interpretation based on my assumptions. I have to be able to falsify interpretations. Really, a wonderful application of science. So lets look more closely at his photo and interpretation. This photo below is taken from his site and his arrow points to what he interprets as the two engines of the train. The primary question he asks was "how can you tell what direction the train was going based on a satellite photo?" I'll get to that question later, but first, lets address Aydin's interpretation of "engines" on the left side of the string of cars:

Here is his closeup:

Aydin's interpretation that these two cars on the far left were engines. I discounted this - why did I? Because in general, locomotive engines have distinct roof-top characteristcs that would stand out even in satellite view:

Here's a slightly more oblique view of an enigne pulling a train of boxcars. Note the distinct patches on the top of the engine.

Big thing is the three large circles on the long end. These radiator fans (some have two, some have three) are extremely common. However, not all locomotives have these fans (this is what I jumped on first, but if one must be objective, we have to determine if this assumption is valid). However, all diesel locomotives have some kind of dark grille on their tops. There are some darker spots on those two cars in the above satellite photos. But, they aren't in distinct circles or rectangles which nearly all locomotives have.

However, there are electrified locomotives which are relatively box-like and don't have obvious grilles on top. But the boxes on top of the locomotives to hold the pantograph (the thing that touches the overhead wires) stands out. The tops of the cars on the far left of the satellite photo are smooth (albeit a little darker than the others).

The only difinitive characteristic that I don't see is the windshield. All locomotives have at least a little break in their shape at the location of the windshiled. Given the lack of radiator grilles and windsheild break, I am interpreting those end cars as boxcars. The beauty of interpretation of observed data is that I might be wrong. I would imagine someone could put forth a set of characteristics that would contradict my interpretations (which is different from Aydins'). It's science with all the warts and wrinkles that personal interpretation brings with it.

So, to answer Aydin's question: what direction is a train going? That's an answer for the next post.

Saturday, March 04, 2006

March Circus Right Here!

Come one, come all. The March installment of the COTS will be here. It's been a slow couple of months for my blog-wise, but productive for research.

Email me: capn.pituitary AT

I'll have a few reminders soon - come on by!