How do cockroaches walk up the wall?
Each fly foot has two fat footpads that give the insect plenty of surface area with which to cling. The adhesive pads on the feet, called pulvilli, come equipped with tiny hairs that have spatula-like tips. These hairs are called setae
Sticky proof
I was watching TV when my son asked this question to me.
I answered casually with my eyes still on TV ," With its legs"
My son : What are you saying Amma? Cant you listen to my question ?
I : Didnt I tell the answer? With its legs..
My son: You and I also have legs..Can we walk up the wall ?
I took my eyes off the TV and turned my attention completely to the 6 year old.
He was looking at me curiously for an answer. Then only it struck me what he wanted to know..
I : Well , now I understand your question..The cockroaches' legs are in such a way that it helps them grip the wall when they walk.
My son : But how ?
I did not have a clear answer.
I said : I would search the internet and get back to you.
I have pasted below one of the best answers I could get. Could be useful for parents to clear the doubts of their children..and even to enhance our own knowledge.
How do insects walk up walls without falling ?
Insects have small claws which can grip tiny bumps or ridges on the wall that we are often unable to see. In addition this, many insects have pads to help them grip walls and ceilings. Usually these pads are on the feet but they are sometimes found on other parts of the leg. The pads often secrete a substance that helps them to stick to surfaces (if you take a small piece of paper and lick it, you will find that the paper sticks to windows - this ability of certain liquids to stick to things is called adhesion). Many insects have hairs on their pads which will aid their grip. The hairs either help the insect grip to microscopic ridges or they make use of the secretions to adhere to surfaces. The pads on some flies contain more than 40,000 of these hairs and enable them to create adhesive forces several times as strong as their own weight.
Walking upside-down requires a careful balance of adhesion and weight, and specialized trekking tools to combat the constant tug of gravity.
Insects have small claws which can grip tiny bumps or ridges on the wall that we are often unable to see. In addition this, many insects have pads to help them grip walls and ceilings. Usually these pads are on the feet but they are sometimes found on other parts of the leg. The pads often secrete a substance that helps them to stick to surfaces (if you take a small piece of paper and lick it, you will find that the paper sticks to windows - this ability of certain liquids to stick to things is called adhesion). Many insects have hairs on their pads which will aid their grip. The hairs either help the insect grip to microscopic ridges or they make use of the secretions to adhere to surfaces. The pads on some flies contain more than 40,000 of these hairs and enable them to create adhesive forces several times as strong as their own weight.
Walking upside-down requires a careful balance of adhesion and weight, and specialized trekking tools to combat the constant tug of gravity.
Each fly foot has two fat footpads that give the insect plenty of surface area with which to cling. The adhesive pads on the feet, called pulvilli, come equipped with tiny hairs that have spatula-like tips. These hairs are called setae
Scientists once thought that the curved shape of the hairs suggested that flies used them to grip onto the ceiling. In fact, the hairs produce a glue-like substance made of sugars and oils.
Sticky proof
A research team from the German Max Planck Institute for Metals Research recently studied more than 300 species of wall-climbing insects and watched them all leave behind sticky footprints.
"There are over one million insect species," team leader Stanislav Gorb told LiveScience. "We suppose that all of them have the secretion, but it is difficult to be 100 percent sure."
Gorb presented the findings at the Annual Meeting of the Society for Experimental Biology in April.
Flies need sticky feet to walk on ceilings, but not so sticky that they get stuck upside down. So each foot comes with a pair of claws that help hoist the gooey foot off the wall.
Flies use several different techniques to get unstuck: pushing, twisting, and peeling its footpads free.
"Methods involving peeling are always the best, because they require less energy to break the contact," Gorb said.
The combination of the feet hairs' rounded tips, the oily fluid, and a four-feet-on-the-floor rule help the inverted insect take steps in the right direction.
"There are over one million insect species," team leader Stanislav Gorb told LiveScience. "We suppose that all of them have the secretion, but it is difficult to be 100 percent sure."
Gorb presented the findings at the Annual Meeting of the Society for Experimental Biology in April.
Flies need sticky feet to walk on ceilings, but not so sticky that they get stuck upside down. So each foot comes with a pair of claws that help hoist the gooey foot off the wall.
Flies use several different techniques to get unstuck: pushing, twisting, and peeling its footpads free.
"Methods involving peeling are always the best, because they require less energy to break the contact," Gorb said.
The combination of the feet hairs' rounded tips, the oily fluid, and a four-feet-on-the-floor rule help the inverted insect take steps in the right direction.
