Tuesday, May 31, 2011

Periodical Cicadas II

Periodical Cicada- 17 year
I recall several returns of the 13 and 17 year periodic cicada over the years in urban settings, but I was totally unprepared for their numbers in a forest.  Walking down our tree lined drive at Bull Creek has become an almost deafening experience while wave after wave burst from the trees, colliding with me in their attempt to escape.

Ash Tree- Click to enlarge
There are two ash trees three inches in diameter beside our garage, literally covered with cicada.  They carpet the trunk, resting no less than two inches apart and hang from every branch and many of the leaves.  Standing on one spot I counted 150 on one side of a tree not including the leaves with a like number on the other side of the tree.  Three neighboring trees held similar crowds.

Walking on down the road the sound diminishes, only to pick up in another 30 feet with a similar cluster of trees loaded with cicada.  Its as though the larvae, after spending 17 lonely years underground sucking sap from tree roots are desperate for company- lots of company.  Then, as the sun disappears below the hill, the cicada disappear and there is again peace in the valley.

After several weeks of wild singing and mating, the females will leave for a little quiet time, slitting open a tree bark repeatedly to deposit clumps of eggs until 400-600 are deposited.  In 6 to 8 weeks the nymphs hatch and drop to the ground to burrow into the soil and find a juicy tree root.  In two years, 98% of them will be dead.

Cicada are on the wrong end of the fast food industry.  Nymphs are eaten by ants and underground arthropod predators like centipedes and ground beetle larvae as well as digging mammals like moles and skunks.  They also may carry the eggs of predatory wasps whose nymphs develop in their body.  Cordyceps fungi also infest them as the do ants and other insects that spend part of their lives in the soil.

Adults in large swarms are a sudden food source for birds, mammals and even a specialized wasp, the Cicada Killer.  The mass emergence of periodical cicada is a defensive strategy called by big brained bipeds "predator satiation."  What the cicada call it or if they even think about it is unknown.

Predator satiation means that when the masses appear all at once, there are more than the combined predators can eat over a short time, so many survive to breed and lay eggs.  This mass hatching strategy can also be seen with hatches of mayflies and termites.

Lots of societies around the world eat cicada.  If you are ready to try them, there are recipes for breakfast, lunch and dinner at Columbia Missourian.com

I would suggest you head for the nearest woods or tree filled park to see and hear this concert which R.L. Jacobs confirms is like Mother Nature's Led Zeppelin concert.  Its your last chance for another 17 years. 

Everything you might want to know about these cicada, known officially as Magicicada Brood XIX, can be found on this magicicada.org web site.   Who knew that they were so organized that they have their own web master?
Good general information of cicada with pictures and sound files are at umich.edu.  
There is extensive information on cicada in general at both 

Monday, May 30, 2011

A Real Head Scratcher

Click to Enlarge
Modern technology has produced outstanding photographs of planets, stars and galaxies but some of the most fascinating images come from the other end of the spectrum.  A book called Microcosmos, created by Brandon Brill is filled with electron microscope pictures of everything from insects to common everyday items.  Many are hard to guess like the picture at the right, a real head scratcher.  Make a guess.

Twenty of these amazing electron microscopic pictures are at green-buzz.net.  Another adventure into the world of small is the microscopic sculpture of art of Walter Wiggan.  How big is big and small is small?  An interesting site of comparison is at Scale_of_Universe.

Oh---about the picture above--- that is a human head louse clinging to a hair.

Sunday, May 29, 2011

Beetles that Bite Back

From LiveScience.com
In a "Man bites Dog" like story, scientists in Israel have reported on a beetle that attacks and eats amphibians of far greater size.  As reported in Livescience.com, the Epomis beetles frequently live peacefully in the same space with the toad or frog in the day.  At night, like a vampire, they strike.

Frogs and toads usually eat insects such as beetles.  In this case, the beetle bites the back of the amphibian which responds violently by trying to shake off the predator.  Once it has cut into the back, its prey is paralyzed and can be eaten at leisure.

The livescience.com site has a video of one attack.  These studies were done at Tel Aviv University in Israel and there are no observations of this behavior in the US - so far.

Friday, May 27, 2011

Shemales of the Wild

Leopard Lacewing butterfly
I came across these amazing pictures on LiveScience.com.  We all are familiar with hermaphrodites which are organisms that have reproductive organs normally associated with both male and female sexes.  These on the other hand are gynandromorphs, a whole horse (or in this case butterfly) of a different color.

You will notice that the wings are distinctly different.  According to Wikipedia, "A gynandromorph is an organism that contains both male and female characteristics."   The right half of the leopard lacewing butterfly pictured here is male while the left half is the typical paler color of the female.

According to the LiveScience posting, "This butterfly emerged from its chrysalis at Iowa State University's Reiman Gardens in 2008.  In almost nine years, Reiman Gardens has received about 163,116 pupae to populate its butterfly wing.  This leopard lacewing is the only gynandromorph butterfly to ever emerge."

Rose-breasted Grosbeak
Gynandromorphs occur when the organism is at the 8 to 64 cell stage.  If it occurs later, the animal is a mosaic with less distinctive changes mixed rather than divided in half  Gynandromorphs occur occasionally in crustaceans and birds as well, as seen in this confused looking Rose-breasted Grosbeak on the right.

There are 13 pictures including a cardinal and a carpenter bee which you can see on the LiveScience posting.

Wednesday, May 25, 2011

Barn Swallows

This is the time of year when our barn swallows go wild.  They return from their South American vacation and reclaim their mud nests that are glued to the rafters of our 100 year old barn.  They originally nested on cliffs but have expanded their numbers and range as humans built structures seemingly made just for them.

Click to enlarge

Barn Swallows (Hirundo rustica) are the most common of the swallow species, occurring in Europe, Asia and Africa as well as the Americas.  Like the swifts, they feed on the wing, flying up to 600 miles a day as they patrol up and down the creek at high speeds grabbing every tiny insect that we can't even see.  I become their new best friend when I run the tractor between the riparian plantings, stirring up a whole new crop of flying insects.  If I stop, they will patiently perch on the fence, waiting for me to flush their next flying crop.

They are less friendly when we enter the barn.  Their nests are filling with eggs and will soon have little peepers peering over the edge of them.  The parents get a little crazy, swooping in and out over my head with an ineffectual mix of "a twittery series of squeaky notes, often with dry rattle in the middle" as heard at allaboutbirds.org.

Swallow in flight
In the morning and evening, they patrol the garden, competing with the dragonflies for their flying meal.  Even at high speeds I can make out their deeply forked tail that is distinctive from the flat tail of the swallows.  This is apparently a big turn-on for lady swallows.  According to whatbird.com, "Females prefer to mate with males that have the longest and most symmetrical tails and a dark red chest color."  They apparently have read the studies which show that longer tailed males are stronger, more disease resistant and live longer.

A few other interesting facts:
  • A group of barn swallows are known collectively as a "kettle" of swallows.
  • The killing of Barn Swallows for their feathers was one of the problems that led to the founding of the Audubon Society and the passage of the Migratory Bird Treaty Act.
  • When building the mud nest, both male and female make up to 1000 trips collecting mud.
Wikipedia  has extensive information on these fascinating neighbors of ours.