Summertime Blues

dragonfly_bluDragonflies hover, swoop and twirl but never walk. They use their legs to trap their insect prey in a tiny six-barred prison before devouring them head-first. When guarding its territory along the water’s edge, this Blue Dasher (Pachydiplax longipennis) grasps a reed or blade of grass and waves his blue abdomen as a warning for other males. Females, in general, aren’t blue at all; they’re black with yellow lines running down their bodies While the name “dragonfly” may be confusing, other names – “snake doctor” or “devil’s darning needle”, for instance – are equally perplexing. No, dragonflies do not treat ailing snakes (or bring them back to life) and the insects don’t sew up any parts of you (although my Grandmother convinced me not to lie with the threat that dragonflies would sew my lips shut if I did). And in case you were wondering about that species name, it means “long wings”… not what you were thinking.

Roly Poly Irony

pillbugWhat’s the #1 killer of Roly Polies (Armadillidium vulgare)? I’ll give you a few hints… it’s not hungry birds, shoes, or tiny heart attacks.

It’s drowning.

The irony is that Roly Polies are crustaceans (not bugs, millipedes, lice or small organic tanks). Their closest relatives include shrimp and lobster.

Roly Polies like moisture – they retreat to damp areas and burrow underground in case of drought. They roll up as a defense against dehydration (and when you poke them). Ah, the wonders of evolution on land. All this protection against desiccation, but no ability to survive in water.

So now that you know Roly Polies are crustaceans, don’t try to rescue them by putting them back in the sea. We’re about 300 million years too late for that!

SOURCE :Population Characteristics of the Terrestrial Isopod Armadillidium Vulgare in California Grassland by Oscar H. Paris and Frank A. Pitelka
Ecology  Vol. 43, No. 2 (Apr., 1962) , pp. 229-248
Stable URL: http://www.jstor.org/stable/1931979

Invasion of the House Finch

HouseFinch_JML

Once upon a time, House Finches (Haemorhous mexicanus) only lived west of the Rocky Mountains. Then, in 1940, a group of captive birds flew to freedom from their New York cages. Their numbers slowly grew until… BOOM… population explosion. Today, House Finches reside throughout the U.S. and Mexico.

There’s a downside to dense populations though – disease. In the 1990s, a bacterium (Mycoplasma gallisepticum) started swirling among groups of House Finches. The infection causes conjunctivitis (like “pinkeye”) in the birds. If you’re a bird with swollen eyelids and crusty build up, you’re not going to be very good at flying or avoiding the neighbor’s cat.

Today, roughly half as many House Finches live in the East compared to 20 years ago.


If you’d like to learn more about House Finch diseases (with gross pictures), visit http://www.birds.cornell.edu/hofi/abtdisease.html.

And if you’d like to see the growth and decline of House Finch populations in your state, check out www.pwrc.usgs.gov/BBS/RawData/ (1)- fun with data!.

1. Pardieck, K.L., D.J. Ziolkowski Jr., M.-A.R. Hudson. 2014. North American Breeding Bird Survey Dataset 1966 – 2013, version 2013.0. U.S. Geological Survey, Patuxent Wildlife Research Center.

Gnarly trees

liveOakBranches of the Live Oak (Quercus virginiana) loop and twist their way toward openings in the forest canopy. Many branches sag down to the ground before stretching back up again.

These low branches help the oak survive in the hurricane-prone regions of the Southeastern U.S. Short, wide trees resist strong winds better than tall, thin ones. Those curvy branches helped the USS Constitution stay afloat during the War of 1812 too. Live Oak limbs were frequently used in ship building due to their natural bends, strength and density.

Penis Bones – no joke!

bacula_JMLCarnivores have ‘em. Rodents and bats have ‘em. Even many primates have ‘em. But not humans.

The baculum (penis bone) is one of the most variable bones in the mammalian skeleton – you can even ID an animal by the shape and size of that one bone. Just like with insect penises, the shapes of these reproductive structures can change quickly in evolutionary terms (Carl Zimmer writes a wonderful post looking at these shifts)
What’s its function?
Well, we’re not 100% sure yet. It may allow males to copulate before being fully, ahem, at attention. Or it may stimulate the female to ovulate. Some bacula grow spiny projections which may, like some insect penises, clear out other sperm before injecting one’s own.
Let’s not leave out the girls!

The penis and clitoris develop from the same structure. So, if the penis has a bone… does the clitoris? You bet! It’s called the os clitoridis (or baubellum).

Snoods, Caruncles, Wattles and Spurs

turkeyThe male wild turkey (Meleagris gallopavo) weighs in as one of the largest birds in North America at around 20 lbs (by comparison, many domestic turkeys weigh twice as much). Females are roughly half the size of the male.

The heads of male wild turkeys are featherless and colorful, with odd sounding structures such as the snood, caruncles, and wattle. Their head can even change color depending on their mood (blue means “Hey, good lookin’!”; red means “I’m ticked off!). The “beard” of the wild turkey grows from the chest and is comprised of filamentous feathers. Males also grow spike-like spurs on their legs, used for fighting.

And the winner is…

maple2_webYour favorite fall foliage comes from the Red Maple (Acer rubrum)!

This tree, native to Eastern North America, has grown even more numerous in the past 100 years. When the Chestnut Blight and Dutch Elm Disease swept through forests, it opened up space for the hardy Red Maple to move in. Add in the tree’s popularity in landscaping and you have one of the most common trees in America!

Beautiful, Delicious, Deadly
Those bright red leaves are lovely and the Red Maple produces maple syrup. But if you were a horse, Red Maples could be deadly. The wilted leaves contain a compound that damages the horses’ red blood cells.

Spooky Spiders

spiderI love Halloween. It’s the time of year when I can leave all the spider webs up around the front stoop and call them decorations.

This harmless garden spider, the Black and Yellow Argiope (Argiope aurantia) is not long for the world. She’ll die soon as the nights grow colder. But I’ll keep an eye on her wee ones in the egg sac she left by the railing. In the spring the baby spiders will hatch out, spin a little silk parachute to catch the breeze and sail away to a new home!

p.s. Haven’t heard of the Black and Yellow Argiope? Well, you may call it the X Spider, Cross Spider, Zipper Spider, Writing Spider, Corn Spider, Banana Spider or Yellow Garden Spider. Whew – darn common names!!