Issus coleoptratus

[neufer]

Zoologger: Transformer insect has gears in its legs
NewScientist 12 September 2013 by Michael Marshall

Species: Issus coleoptratus
Habitat: throughout western Europe, often hanging around on ivy plants

<<For a disconcerting experience, consider how mechanical you are. Humans may be conscious beings with higher feelings, but really we're just fancy machines with joints, motors, valves, and a whole lot of plumbing. All animals are the same. Hundreds of gizmos have evolved in nature, many of which our engineers merely reinvented. Nature had rotating axles billions of years ago, in the shape of bacterial flagella. And weevil legs beat us to the screw-and-nut mechanism.

The insect Issus coleoptratus is another animal with an unexpected bit of machinery hidden in its body. Its larvae are the first animals known to have interlocking gears, just like in the gearbox of a car.

In high gear Issus coleoptratus is a type of planthoppers – a group of insects known for their prodigious jumping. It takes off in just 2 milliseconds, and moves at 3.9 metres per second. "This is a phenomenal performance," says Malcolm Burrows of the University of Cambridge. "How on earth do they do it?"

Burrows first ran into the larvae of Issus coleoptratus in a colleague's garden. "We were poking around and there were these bugs, jumping around like crazy." He took a closer look, and noticed that each larva had meshing gears connecting its two hind legs. The gears had been seen before, by a German biologist called K. Sander, but his 1957 paper isn't even on the internet.

The bulb at the top of each hind leg has 10 to 12 teeth, each between 15 and 30 micrometres long. Effectively, each hind leg is topped by a biological cog, allowing the pair to interlock, and move in unison.

Click to play embedded YouTube video.

Working with Gregory Sutton of the University of Bristol, UK, Burrows filmed the gears at 5000 frames per second and confirmed that they mesh with each other. The two hind legs moved within 30 microseconds of each other during a jump. Burrows and Sutton suspect that the gears evolved because they can synchronise the leg movements better and faster than neurons can. Other animals have gears, but not gears that mesh, says Chris Lyal of the Natural History Museum in London. "When you look at [I. coleoptratus's gears], you wonder, why can't anything else do that?" he says.

The German study from 1957 claims that all 2000-odd planthoppers have gears. "I've looked at about half a dozen, and they all have them," says Burrows. "I'd be hesitant to say no other animal has them," says Burrows. "But they haven't been described."

There's one other mystery. Only larval planthoppers have gears. When they become adults, they lose them. "Adults still jump very well," says Burrows, and their legs are synchronised, but instead of gears, they rely on friction between the trochanters. "Why do they throw away a neat mechanism?" It might be that gears are easily broken, and as soon as one tooth is sheared off, the mechanism doesn't work as well. "For an adult that can't moult again, that's going to be a problem." Friction may be a crude way to synch your legs, but it might also be more robust than fragile gears.>>

[geckzilla]

Some assassin bugs have a cog sticking out of their thorax, but it's just to make it look unpalatable, I think. Different function but very similar in shape. https://en.wikipedia.org/wiki/Wheel_bug

[Beyond]

Only two posts, and already this thread is starting to bug me

[geckzilla]

Bugs are awesome. I came across this guy's blog recently. It's really fun to read.
http://bugeric.blogspot.com/

(Why does it seem like there are a lot of scientists in Colorado?)

[Beyond]

And at least one of them is nicely "Abominable". Must be something in the air.

[neufer]

Bugs are awesome. I came across this guy's blog recently. It's really fun to read.
http://bugeric.blogspot.com/

(Why does it seem like there are a lot of scientists in Colorado?)

And at least one of them is nicely "Abominable".

Must be something in the air.

A lingering North American monsoon

A 400mb. Water Vapor Map for 16:00 UTC September 13, 2013

<<The North American Monsoon is not as strong or persistent as its Indian counterpart, mainly because the Mexican Plateau is not as high or as large as the Tibetan Plateau in Asia. However, the North American Monsoon shares most of the basic characteristics of its Indian counterpart. There is a shift in wind patterns in summer which occurs as Mexico and the southwest U.S. warm under intense solar heating. As this happens, the flow reverses. The prevailing winds start to flow from moist ocean areas into dry land areas.

The North American monsoon is associated with an area of high pressure called the subtropical ridge that moves northward during the summer months and a thermal low (a trough of low pressure which develops from intense surface heating) over the Mexican Plateau and the Desert Southwest of the United States. The monsoon begins in late May to early June in southern Mexico and quickly spreads along the western slopes of the Sierra Madre Occidental, reaching Arizona and New Mexico in early July. The monsoon extends into the southwest United States as it matures in mid-July, when an area of high pressure, called the monsoon or subtropical ridge, develops in the upper atmosphere over the Four Corners region, creating wind flow aloft from the East or South-East. Flash flooding is a serious danger during the monsoon season. Dry washes can become raging rivers in an instant, even when no storms are visible as a storm can cause a flash flood tens of miles away (never camp in a dry wash in the desert). Lightning strikes are also a significant danger. Because it is dangerous to be caught in the open when these storms suddenly appear, many golf courses in Arizona have thunderstorm warning systems.>>

[geckzilla]

Heh, yeah, Phil Plait has a blog entry on the flooding, too.

[neufer]

Heh, yeah, Phil Plait has a blog entry on the flooding, too.

• Bad Astronomer, Bad!

Click to play embedded YouTube video.

Boulder Is Flooding
By Phil Plait, Sept. 12, 2013, at 1:30 PM

UPDATE, Sept. 12, 2013, at 18:00 UTC: In the video I mentioned I felt pretty safe on the overpass because the infrastructure was sound. However, I hadn't considered flash flooding. Debris has been building up in the creeks upstream, and if those let go, it can create a flash flood, a very dangerous wall of water. One has been reported at Logan's Mill in Four Mile Creek already.

PLEASE, everyone, stay away from anywhere water is flowing, especially near creeks. They may look safe for now, but that can change extremely rapidly.

[Correction (Sep. 13, 2013 at 04:00 UTC): In the text and video I mistakenly said this footage was northwest of Boulder, when it's actually northeast — I suspect it's because I was facing south the whole time, and got my directions backwards. I generally have an excellent sense of direction, so this is a little embarassing. I have fixed the text, but the video is annotated internally and so my error will be enshrined there forever.]

[Rin]

Can anyone tell me if there is a type of issus found in North America? I have seen one of these insects but can't find anything stating that they even exist on this continent.

[geckzilla]

Some Issidae live in NA from what I can gather from Bug Guide (Taxonomy, Images) but no Issus.