Friday, July 29, 2011

The Truth Behind Daddy Longlegs

By: Lacy Sellent, Writing Fellow at the Cable Natural History Museum
           
Growing up, I heard a lot of “facts” about the natural world.  One particular “fact” about daddy longlegs really stuck in my head.  The rumor was that if daddy longlegs had mouths big enough to bite humans they would the most poisonous spider in the world.  This is something I believed for quite some time—until I learned the real truth…   

One problem with this legend is that daddy longlegs (also known as harvestmen) are not poisonous to humans.  In fact, they have no venom whatsoever.  However, it is true that their mouths are too small and their jaws are too weak to bite humans.  Apart from not being venomous in the first place, another reason why daddy longlegs are not the most poisonous spider in the world is because they’re not even spiders!  Daddy longlegs and spiders are more like cousins to each other.

Scientists classify all living things in a hierarchical system with seven or more different levels.  Organisms are put into groups based on shared characteristics, which often reflect how closely they are related to each other.  The top category is the broadest and then each subsequent category gets more specific. Spiders and daddy longlegs both are in the kingdom Animalia, the group to which all animals belong. They also share the phylum Arthropoda with insects and crayfish. They share the class Arachnida with ticks and scorpions. The next category is order. All spiders make up the order Araneae, while daddy longlegs make up the order Opilione. That order is divided further into families, genera, and finally into over 6,400 individual species of harvestmen has been discovered worldwide.

Both spiders and daddy longlegs have a hard outer shell called an exoskeleton instead of a backbone, eight jointed legs, and segmented bodies. Unlike spiders, daddy longlegs are not capable of spinning webs. They don’t even have any silk glands!  And while spiders have eight eyes, daddy longlegs only have two. They also differ from spiders in their eating habits. Daddy longlegs catch food and eat it outside their mouth, because that’s where their teeth are located.  After a meal, daddy longlegs clean up from the messy task.  After a quick swipe of their legs through their jaws the daddy longlegs is clean and ready to get on with its day. Or, rather, its night. 

Daddy longlegs generally hunt at night—searching through leaves and other debris.  Daddy longlegs will eat anything from plant matter to worms and small insects. They can be handy around a garden, because they’ll help keep pesky insects, such as aphids, away. The name Opilione (to which the daddy longlegs belongs) is Latin for “aphid sucker.”

While out looking for food, daddy longlegs use their legs to sense danger. Any vibration made by approaching trouble is picked up through their extra-sensitive legs. These legs are also used for tasting and smelling. If a daddy longlegs finds itself in trouble, it has two legs that can give off a nasty odor.  Not many predators care for a smelly dinner. 

They also have another trick—when trapped, they can release the captured leg!  Once a daddy longlegs realizes there is no other way out, it uses a special muscle to dislodge the leg from its body. Then the muscle closes around the stump and the daddy longlegs scurries off to safety.  Meanwhile, the foe is left with a squirming leg.  The lost leg may twitch for several minutes.  This distracts the predator—ensuring the daddy longlegs a safe getaway.  

Daddy longlegs are harmless creatures that are often misunderstood.  They are not poisonous, and they are not spiders.  We don’t need to fear them.  We just have to get to know them.

For over 44 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility in Cable at 13470 County Highway M. The new exhibit, The Joy of Birds: Feathers in Focus opened in May, 2011. Find us on the web at http://www.cablemuseum.org/ to learn more about our exhibits and programs. Also discover us on Facebook, or at our blogspot, http://cablemuseumnaturalconnections.blogspot.com/.

The Stick that is Not a Stick…

By: Lacy Sellent, Writing Fellow at the Cable Natural History Museum


Before heading off on a hike in the great outdoors, you may want to learn more about walking sticks.  Knowing the typical length of a walking stick, along with knowing where to look in order to find one, are both good places to start.  It also may be beneficial to know what they eat…Wait, what?

As you may have noticed, I’m not talking about a wooden walking stick.  No, I am talking about the actual creepy crawly insect in the order Phasmatodea.  The walking stick is an insect that tricks predators, such as birds, into thinking that it is just a stick—not a tasty meal.  Depending on the species, the walking stick may be green or brown.  The green species match the color of the leafy bushes that they hide in.  The brown ones can blend in among the twigs and branches of trees.   

These insects (at least the ones in Wisconsin) range in size between half an inch and several inches—depending on the species, gender, and age of the insect.  The male is shorter than the female, but both sexes can reach some amazing lengths.  Some species from across the globe have been known to grow as long as twenty-one inches!  Here in Wisconsin we won’t be seeing any twenty-one inch walking sticks, but we can still observe their amazing natural disguise.   

The walking stick, like most living things, has excellent physical and behavioral adaptations that help it survive in its habitat.  One clever behavioral adaptation of the walking stick is to sway back and forth when perched on a twig or leaf.  The swaying motion helps it to better mimic how a tree branch moves in the wind, and adds accuracy to its disguise.  Not only does the walking stick have the benefit of physically looking like a stick, but it also acts like one!

During the day is when you would be most likely to spot one swaying with the breeze. This is because the walking stick is an insect that does its moving around mostly at night.   At night it will “branch out” to forage for food.  This insect is an herbivore, so it’s not uncommon for them to feed from the same plants that also provide them with shelter. 

The distinguishing characteristics of this insect don’t stop at its use of camouflage.  The walking stick is also one of the few species to reproduce without the aid of a male.  All a female has to do is lay the eggs and they will all be born female.  The males are not only smaller in size, but also fewer in number.  If a male does happen fertilize the eggs there is still only a fifty-fifty chance that some of the eggs will be male.  Because of this unique characteristic, there are some species of walking sticks that are entirely female. 

The walking stick is truly a fascinating insect—and it is one that lives in your own backyard!  The next time you walk by a bush, look closely.  With a watchful eye, you may be able to spot the stick that is not a stick.

For over 44 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility in Cable at 13470 County Highway M. The new exhibit, The Joy of Birds: Feathers in Focus opened in May, 2011. Find us on the web at http://www.cablemuseum.org/ to learn more about our exhibits and programs. Also discover us on Facebook, or at our blogspot, http://cablemuseumnaturalconnections.blogspot.com/.


Leaves of Three

By: Lacy Sellent, Writing Fellow at the Cable Natural History Museum


As a kid, there was one plant that my parents always warned me about—poison ivy.  It never looked all that bad to me.  For the most part the leaves were only about two or three inches long.  The plant didn’t even look sharp or prickly like a thistle.  Well, it didn’t take me long to learn to follow my parents advice—that when I saw “leaves of three,” I needed to “leave them be”.

All it takes is one little brush against your leg and within a few days you’ll break out in a nasty rash.  It will itch and may even ooze a bit.  Yeah, I know, it’s not very pleasant.  This is actually a type of allergic reaction.  It’s caused by urushiol, a type of oil made by the plant.  The leaves, the stem, and even the roots all have this pesky stuff on them.

On the bright side, if you realize you’ve come in contact with poison ivy you may be able to spare yourself from its not-so-nice side effects.  By washing your skin with alcohol—within ten minutes after touching it—you can still rid yourself of the oil.  Washing with water will also help.  If you are not able to wash your skin within ten minutes (or don’t realize that you’ve come across any poison ivy) then the oil is already soaked up into the skin.  At this point, it can no longer be washed off.  The main thing is to try to wash everything that touched the plant as soon as possible.  This includes your shoes and clothing. 

Your clothes can not absorb the urushiol in the same way that your skin can.  Because of this, the oil on your clothes can cause rashes for months after your first contact. Although many believe the rash itself is catchy, the rash is more likely to be spread through fabrics.  A shared pair of gardening gloves may be to blame for the spread of a rash from one person to another.    

Another good thing to know is that not everyone who touches poison ivy will break out in a rash.  But there’s a catch.  The more times you come in contact with poison ivy, the worse your reaction may become.  For example, the first time you touch poison ivy, you may not see a rash until over a week later (if you ever see one at all).  After a few more run-ins with poison ivy, you may start to see a rash in as little time as a day or two. 

What’s really creepy about poison ivy is that, according to Dr. Lewis Ziska (from the U.S. Department of Agriculture), it has begun to grow larger and more poisonous than ever before.  Poison ivy plants are now capable of growing twice the size today as they were back in 1901.  This is partially due to more carbon dioxide in the atmosphere.  Since carbon dioxide is what plants eat, poison ivy (among other nuisance plants, such as poison oak) is able to produce more food.  When combined with the results of logging (which opens up a forest—giving more light for the poison ivy to grow) and other land use activities, we could be creating the perfect environment for poison ivy.

On the flip side, poison ivy is a native plant to Wisconsin and, therefore, has its part to play in the Northwood’s environment.  Everything from bluebirds and robins to turkeys and crows either eat the berries of the poison ivy plant (which are present in late summer) or they use the plant as cover.  Even deer will munch on poison ivy, only they’ll mostly eat the leaves.  In some cases, people like having a bit of poison ivy around because then the deer eat that instead of their garden.

As you explore the woods this summer, keep in mind that nature can be fun and we also need to be aware of its dangers.  Now that you know more about poison ivy, get out there and enjoy your summer—just stay away from those leaves of three!

For over 44 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility in Cable at 13470 County Highway M. The new exhibit, The Joy of Birds: Feathers in Focus opened in May, 2011. Find us on the web at http://www.cablemuseum.org/ to learn more about our exhibits and programs. Also discover us on Facebook, or at our blogspot, http://cablemuseumnaturalconnections.blogspot.com/.

Flash of the Firefly

By: Lacy Sellent, Writing Fellow at the Cable Natural History Museum

One of my favorite activities to do in the summer is to set out on a lightning bug ride.  On a calm, peaceful night my mom and I will make our way to the barn, saddle up our horses, and head out into the night.  The sharp crunching of hooves on gravel turns to a light thudding as our horses make their way from the barn to the hay field.  I take note of the immense darkness in which I am a part of, though do not fear.  Within that darkness there are tiny specs of light…

I can feel the grass brush against my legs as we continue to move forward.  I look up and see a vast array of stars lighting up the sky—then I look around me and I see that, like the sky, the field has become scattered with little lights.  The lights surround us.  Everywhere we look there are lightning bugs—the field is alive with them. 

Blink.  Blink-blink.  Blink.  If watched closely, the flash of each firefly repeats a special pattern.  These patterns are used by fireflies (also known as lightning bugs) to communicate with each other.  The flashing pattern changes depending on the temperature and the species of firefly.  On cool summer nights a male may only emit light every ten seconds.  In contrast, warmer weather increases the speed of the blinks.  The females notice the blinks, and respond by mimicking the flash pattern of a chosen mate.  It is through this process that fireflies continue to exist—the flash of the firefly is not only fun to watch, but it also plays an important role in the survival of this unique beetle.   

Today new research is pointing toward one danger that could jeopardize the lives of fireflies.  That danger comes in the form of light pollution.  From our fourteen-watt patio lights to the little lights that brighten our garden paths—all these lights make it difficult for the fireflies to communicate.  These artificial lights shine brighter than the much dimmer light of the male firefly, making it hard for the female to find the male. 

In a situation such as this, you may wonder: what can I do?   How can I help the fireflies?  One way would be to remove the light sources from your yard.  This can be done by taking out the garden lights, turning off patio lights, or by pulling the shades of a lighted room.  If you want to see the actual beetle itself, you could grab some blue tissue paper and wrap it over the lens of a flashlight.  This creates a blue light which is not as misleading to the fireflies. 

The way you landscape your yard is another way to create a welcoming environment for the fireflies.  Fireflies find safety in long grass, so it may be beneficial to set aside a section of yard for the fireflies.  Also, since one of the earlier stages of a firefly’s life is a grub, it may be a good idea to refrain from using pesticides (which target and kill grubs). 

This summer I encourage you to embrace your inner child and head outside.  See how many fireflies you can spot!  If you catch any of the fireflies, it is important to remember that they need to stay moist.  Putting fireflies in jars may dry them out. To prevent this, place a damp paper towel in the bottom of the jar.  

By following these tips, we can help protect the fireflies of today in hopes of preserving them for the generations of tomorrow.  The next time you visit the great outdoors, be sure to keep an eye out for the flash of the firefly.

For over 44 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility in Cable at 13470 County Highway M. The new exhibit, The Joy of Birds: Feathers in Focus opened in May, 2011. Find us on the web at http://www.cablemuseum.org/ to learn more about our exhibits and programs. Also discover us on Facebook, or at our blogspot, http://cablemuseumnaturalconnections.blogspot.com/.

Friday, July 1, 2011

Everything else in the Universe

I arrived in northern Wisconsin in the dead of winter.  It was the last week of this past January.  Snow blanketed the ground, with bare twigs poking through and gray clouds hovering above.  I wasn’t fooled.  Having spent four years in Ashland as a Northland College student, and having lived in several other wintery places, I have come to appreciate the joy of the changing seasons.  You’ve all been reading about those seasonal changes, known as phenology, in NatureWatch articles for the past 20 years.  As the new Naturalist/Educator, I am honored to begin writing the Museum’s weekly column.
 With a new voice comes a new name.  Throughout my life as an educator and naturalist all across the U.S., one theme has been consistent: connections.  I love discovering connections in nature: how algae and fungus work together to create lichens; how mosquitoes benefit from the bug-catching skills of the carnivorous pitcher plant; how yellow-bellied sapsuckers provide food for the early spring hummingbirds; how blueberries, wintergreen, and Pacific madrone trees are related by genetics and habitat.  But knowing about these connections is an empty accomplishment if I can’t share my excitement for nature with others.  So my interest in connections also manifests itself in a desire to connect people, including myself, to nature.  Gathering wild edibles, enjoying silent sports, gardening, and just experiencing wonder at the world make me feel a part of nature, instead of apart from it. 
One of the natural connections I’ve made since moving back to Wisconsin is with the students, faculty and staff at Northland College.  Many of my friends and classmates at Northland were interns and Naturalists at the Museum.  They all received excellent mentoring and gained valuable experience.  I hope to continue that tradition.  In my short time here I’ve already hired three different Northland students for various internships and fellowships.  One of those is Lacy Sellent, a senior in Humanity and Nature Studies with a minor in Writing, from Cumberland, WI.   She will be writing the Natural Connections column for several weeks as a part of our Focused Fellowship program.   It has been my pleasure to work with her, I’m sure you will enjoy her writing. 
This fall, before the snow blankets the woods once again, I will return to share my favorite connections with you.   Making connections is natural, and once you begin to see them, you see them everywhere.  In the words of John Muir: "When we try to pick out anything by itself, we find it hitched to everything else in the Universe."
For over 44 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility in Cable at 13470 County Highway M. The new exhibit, The Joy of Birds: Feathers in Focus opened in May, 2011. Find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Also discover us on Facebook, or at our blogspot, http://cablemuseumnaturewatch.blogspot.com/.