Category: Biology

Smelling Feet or Smelly Feet?

3/7/2023

Dorothy Hinshaw Patent
Nature’s Animal Ambassador

Do your feet sometimes smell rotten? Do you wish you could toss out your shoes and start with a new pair? We make jokes about smelly feet, but smell and feet have a very different relationship among some insects.

Take butterflies. Have you ever watched a butterfly flit over a plant, gently touch its feet to a leaf, and then fly on to the next leaf? That butterfly isn’t being picky about where to land. It’s hunting for the right kind of leaf for laying its eggs. It’s “smelling” the leaf with its feet!

Actually, we need to qualify that statement a bit. Some writers will say the insect is “smelling” the leaf while others may write that it’s “tasting” the leaf. Smelling and tasting are forms of “chemoreception,” or sensing of chemicals. Smell usually refers to sensing from a distance while tasting generally means actually touching the nerve cells that sense a chemical.

We humans have cells in our noses that send messages to our brains about chemicals in the air. We call that our sense of smell. We have cells on our tongues that sense chemicals dissolved in liquid in our mouths. That’s taste.

That butterfly doesn’t have a nose, and its mouth is a long tube for sucking up nectar from flowers. Its chemoreceptors are elsewhere, like on its feet, around its mouth, and on its antennae. Most butterflies lay their eggs on the plants that the hatched caterpillars will eat. Some species are very specific about what plants their young can feed on. Take the postman butterfly, which lives in Central and South America. Its caterpillars can only survive on certain species of passionflower vines. Other species are poisonous to their offspring.

The female postman butterfly has dozens of special nerve cells on her feet called “gustatory sensilla.” Scientists think that when she touches gently down on a leaf, these cells can sense chemicals there that would be poisonous to her caterpillars. She avoids laying eggs on those leaves. But when she finds a plant that will nourish her young, she’ll alight and lay her eggs.

Now take your shoes off and move your feet around on the floor. The only nerve endings on your feet are ones that sense touch. But then, you don’t need to be able to smell the ground you walk on. Imagine how gross it would be if your feet could smell the insides of your socks and shoes—yuck!

In these photographs taken through a microscope, you can see the sensory sensilla (arrow) on the feet of the female butterfly on the right, which the male on the left doesn't have. From PLoS Genet. Jul 2013; 9(7): e1003620.

Above: Postman butterfly feeding Right: Female postman butterfly laying an egg. As you can see from these two photos, the postman butterfly can have a variety of color patterns. From Heliconius.org

A dog’s nose is 300 times more powerful than a human nose, so it’s no wonder that dogs use their incredibly advanced sense of smell to do some very important jobs. In Super Sniffers, Dorothy Hinshaw Patent explores the various ways specific dogs have put their super sniffing ability to use: from bedbug sniffers to explosive detectors to life-saving allergy detectors . . . and more. This dynamic photo-essay includes first-hand accounts from the people who work closely with these amazing dogs. For more information, click here.

Dorothy Hinshaw Patent is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.

MLA 8 Citation
Patent, Dorothy Hinshaw. "Smelling Feet or Smelly Feet?" Nonfiction Minute, iNK
Think Tank, 23 Jan. 2018, www.nonfictionminute.org/the-nonfiction-minute/
Smelling-Feet-or-Smelly-Feet.

0 Comments

Food Chain Poems

2/15/2023

3 Comments

Stephen Swinburne
Lifelong Naturalist

When I take a big bite into a hamburger, I am taking part in a food chain. When energy moves from one living organism (hamburger) to the next (me), scientists call this path or chain the Food Chain. Every living thing needs food. Food provides energy for plants and animals to live.

            Food chains begin with plants using sunlight, water and nutrients to make energy in a process called photosynthesis. There are lots of different kinds of food chains— some simple, some complex. An example of a simple food chain is when a rabbit eats grass and then a fox eats the rabbit. I think food chains are so interesting, I’ve written some poems about them.

A Shark is the Sun

Shark eats tuna,
Tuna eats mackerel,
Mackerel eats sardine,
Sardine eats zooplankton,
Zooplankton eats phytoplankton,
Phytoplankton eats sun.
So...shark eats sun.

            In every food chain there are producers, consumers and decomposers. Plants make their own food so they are producers. Animals are consumers because they consume plants or animals. Decomposers have the final say as they break down and decompose plants or animals and release nutrients back to the earth. Animals can be herbivores (plant eater), carnivores (meat eater) or omnivores (plant and meat eater). What are you?

Why Can’t I Be On The Top?

I don’t like the bottom,
I want to be at the top.
I’m tired of being crushed and stomped
and chewed into slop.
Why can’t I be the tiger
with claws as sharp as shears,
With a roar as loud as thunder
To threaten trembling ears?
Who designed this food chain?
Is there a chance I can opt out?
At least I’m not a plankton
Floating all about.

   I hope you are happy with your place in the food chain. If not, you might want to sing along with the Food Chain Blues.

Food Chain Blues

Mama said be careful,
It’s a risky world outside,
Dangers lurking everywhere,
Hardly a place to hide.
She said some of us get eaten,
And some of us survive.
Count yourself quite lucky,
If you make it out alive.
We’re stuck in this cruel cycle,
Nature’s red teeth and claws.
You wanna do your best,
To stay clear of someone’s jaws.
I got the food chain blues
I got the food chain blues
Someone’s gonna eat me.
I got the food chain blues!

This is a simple version of the food chain, which can also be called a "web" especially for organisms that are omnivore

Omnivorous author and his wife, Heather.

For more of Steve's poems about creatures check out Ocean Soup. It even has its own web page here.

Steve Swinburne is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.

MLA 8 Citation
Swinburne, Stephen. "Food Chain Poems." Nonfiction Minute, iNK Think Tank, 8
Mar. 2018, www.nonfictionminute.org/the-nonfiction-minute/Food-Chain-Poems.

3 Comments

Here Come the Cicadas

2/8/2023

3 Comments

Laurence Pringle
celebrating nature, inspiring good writing

Almost every spring an amazing event in nature happens in parts of the United States. Huge numbers of insects called periodical cicadas emerge from the soil. For a few weeks they fill the days with loud buzzing calls.

Every summer you can hear the calls of some kinds of cicadas, but periodical cicadas are different. They exist only in the eastern two-thirds of the United States, and have the longest of all insect lives. Some periodical cicadas live 13 years, others 17 years, with nearly all of that time spent underground. Young cicadas, called nymphs, sip water and nutrients from tree roots. The nymphs count the years, probably by sensing changes in tree sap, as it is affected by the seasons of each year.

When their countdown ends and soil warms in the spring, millions of cicada nymphs dig out. They climb posts, bushes, and trees, and cling there. Their nymph "skins" split open and adult cicadas wriggle free. Finally, after many years underground, they are out in the sunshine. They can fly, and the buzzing noises of males attract females. It is a noisy and hectic time in their lives. They have just a few weeks to mate and produce the next generation. Once females lay eggs in tree twigs, all of the adults die. Soon after, tiny nymphs hatch from the eggs. They drop to the soil, borrow in, and begin to sip juices from tree roots. The nymphs grow slowly, counting the years until they will have their own time in the sun.

Nearly every year, one or more populations, called broods, of periodical cicadas emerge. Seventeen year cicadas live mostly in the Northeast and Upper Midwest. Thirteen year cicadas are most common in the South and Lower Midwest. Some broods emerge in parts of just a few states. Some years, a more widespread brood emerges in parts of fifteen states. Notice that I say "parts" of states. These cicadas don't roam around. The nymphs go underground in the same places where their parents emerged. You will find them in one town but not another, in one neighborhood but not another.

Some people call cicadas "locusts," but locusts are a kind of grasshopper that eats plants. Cicadas do not chew on plants. They are harmless, fascinating creatures. And, once in a great while, they give us a rare and awe-inspiring animal spectacle.

A time sequence photo of a cicada molting (shedding its skin). Wikimedia Commons

Face to face with a periodical cicada: you can tell because these remarkable North American insects have black bodies and red eyes. All cicadas have five eyes, with three tiny ones that form a triangle between two big ones. Wikimedia Commons

Visit the great website, Cicadamania, which has high praise for this book: "Definitely the best cicada book for kids. Adults will appreciate it as well, as it is well written, factually accurate, and beautifully illustrated."
You can read more about Larry's fascination for these creatures on his website.

MLA 8 Citation
Pringle, Laurence. "Here Come the Cicadas." Nonfiction Minute, iNK Think Tank,
23 Apr. 2018, www.nonfictionminute.org/the-nonfiction-minute/
Here-Come-the-Cicadas.

3 Comments

Alligator Smiles

1/30/2023

3 Comments

Stephen Swinburne

Lifelong Naturalist

Alligators are one of the world’s most feared predators. With rows of dagger-sharp teeth, a muscled reptilian body, a dinosaur face and eyes, alligators frighten yet fascinate people. Scientists are working hard to understand this modern-day reptile.

Dr. Daphne Soares, biology professor at the University of Maryland, was intrigued by the hunting ability of the alligator. She knew alligators have keen eyesight and excellent hearing but there was something else that made them such efficient predators, the king of the swamp. Careful focus on the dark bumps all over the animal’s upper and lower jaws led her to conclude that these bumps “were very sensitive tactile organs that can detect ripples in the water.” The ability to feel waves or ripples is one of the many features that makes the alligator an excellent predator. Once the alligator detects ripples, it swims swiftly and silently in the direction of the prey.

Alligators are carnivores. They seize and hold their prey with sharp teeth. Small quarry, such as fish and ducks, are swallowed hold. Larger victims are shaken apart into smaller, bite size pieces. Gators have between 74 and 80 teeth in the jaws at a time. When their teeth get worn down, they are replaced with new ones. Imagine that! No need for a dentist. Alligators can go through 2,000 to 3,000 teeth in a lifetime.

Alligators are a rare success story of an endangered species saved from the brink of extinction. As late as 1950s, alligators were hunted for meat and hide. They were placed on the Endangered Species list in 1967, and now thrive in the freshwater swamps and wetlands of the southeastern United States.

A smiling American Alligator displaying the bumps around its upper and lower jaws.

Steve wrote, Sea Turtle Scientist after spending time with Dr. Kimberly Stewart, “the turtle lady,” and describes her work on St. Kitts with endangered loggerhead sea turtles.

Steve is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.

MLA 8 Citation
Swinburne, Stephen R. "Alligator Smiles." Nonfiction Minute, iNK Think Tank, 29 Sept. 2017, www.nonfictionminute.org/the-nonfiction-minute/alligator-smiles.

3 Comments

Dear Friend

1/26/2023

1 Comment

Cheryl Harness
She’s historical

Picture this: It’s cold gray October 1918 in France, in the Argonne Forest. World War I has been going on for four hideous, deadly years. You and about 500 of your fellow Americans are smack in the middle of a MASSIVE battle. You’re running out of food and ammo. Shells are EXPLODING all around you and some of them are American! Those guys don’t know where you and your buddies are, trapped in a hillside valley, surrounded by enemy Germans!

          How can Major Charles Whittlesey, the commander of this lost battalion, let those other Americans know where his unit is? They’re cut off from the telegraph wires; so what, wave a flag? That’ll just draw more enemy fire! The messengers he’d sent had been shot or captured. How about homing pigeons? In this awful war, more than a 100,000 of them were used to carry battlefield messages. The major had sent all but one of his pigeons only to see them shot out of the sky. Finally, the desperate officer calls for his last one, named Cher Ami, the French words for Dear Friend.

          Major Whittlesey scribbles out a message: “We are along the road parallel to 276.4.Our own artillery is dropping a barrage directly on us. For heaven’s sake, stop it.” He rolls the scrap of paper, stuffs it into the tiny silver canister attached to Cher Ami’s leg, and sends him up and away. This pigeon has flown 11 successful missions— will he make it now? He must!

          The Germans fire.

          Cher Ami falls! He’s hit!

          But he beats and flaps his wings, gains altitude, and flies 25 miles. Despite being blinded in one eye and shot in his bloodied breast, Cher Ami delivers the critical message, still attached to his leg, dangling by a bloody tendon. And 194 American soldiers are saved by their brave dear, feathered friend. For his heroic service, Cher Ami was awarded France’s highest medal, le Croix de Guerre (the Cross of War).

          In the months after the war ended, on November 11, 1918, ocean liners carried Cher Ami and many thousands of other veterans to America. He continued to be treated, but in the end, his injuries were too serious. Cher Ami died on June 13, 1919.

          Back in the USA, Major Charles Whittlesey gave speeches about the war. He said nothing about any sorrow or awful memories, so no one knows just why he jumped off a ship to his death in the sea, late one night in November 1921. But the memory of soldiers’ heroism and of one bird’s stubborn courage will never die.

Cher Ami, stuffed and on display, minus his teeny wooden leg, carved by a fellow veteran. Wikimedia

Major Charles White Whittlesey was considered one of the greatest American heroes of the First World War. A Harvard-educated attorney working on Wall Street, he took a leave from his company and enlisted in the army as soon as the war began.

Cher Ami saved what the press called the “Lost Battalion,” a unit of about 200 men. This US Army Signal Corps photo shows them just after reaching friendly territory.

Cheryl's Latest book is Flags Over America. Click here to find out more about the book or click here to find out more about the author.

MLA 8 Citation
Harness, Cheryl. "Dear Friend." Nonfiction Minute, iNK Think Tank, 8 01 2018, www.nonfictionminute.org/the-nonfiction-minute/dear-friend.

1 Comment

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Smelling Feet or Smelly Feet?

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Here Come the Cicadas

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