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  would you like to french kiss a flower my dear?

"This is the only animal in the world that we know of that resembles a flower blossom to attract prey," O'Hanlon added. "There are other animals that are known to camouflage amongst flowers and ambush prey items, but they do not actually attract the pollinators themselves the flowers they sit on are the attractive stimulus. The orchid mantis is unique in that the mantis itself is the attractive stimulus. This means the mantis can sit away from flowers, perhaps on leaves or bark, and still lure in pollinators."

Orchid mantis (Hymenopus coronatus) of the Malay peninsula.		Orchid Mantis Hymenopus Coronatus, image: Thomas Marent
	Left: Indian preying mantis. Image: Shiva shankar
	Right: A praying mantis that has evolved to be dressed in bark camouflage.

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the fastest horse on earth - with added stealth technology

"The seahorse is one the slowest swimming fish we know of, but it's able to capture prey that swim at incredible speeds,"
—
"Seahorses dine by a method known as pivot feeding. Their arched necks act as a spring - allowing them to rapidly rotate their heads and suck their prey in. But this suction only works at short distances. The effective strike range for seahorses is about 1mm. And a strike happens in less than 1 millisecond."

beetles are astronomers and pigeons have gps

“To test whether the beetles were using the stars as a navigational aid, scientists put the beetles into a dung-rolling course and filmed their behavior. The beetles were able to move in a straight line on moonlight nights and also on moonless nights when the Milky Way was visible. When the sky was overcast, the beetles were unable to roll the dung balls in a straight line. When the beetles had tiny visors taped onto their heads to block their view of the night sky, they spent their time wandering aimlessly.

“Next, they tested their speed on a 2 meter platform. On nights when the Milky Way was visible, the beetles were able to cross the platform in as little as 40 seconds. On cloudy nights, it took the beetles nearly 2 minutes to cross the platform.

“Lastly, scientists tested the beetles inside of a planetarium The dung beetles moved more efficiently when the ground was lit by the light of the Milky Way. When the ground was lit by the light of only a few bright stars, the beetles performed worse.” [Quoted from earthsky.org]

“The researchers found that each neuron had its own characteristic response to the magnetic field. In fact, each gave a kind of 3-D compass reading along the familiar north-south directions in addition to pointing directly upward or downward. Each cell also showed sensitivity to field strength, with the maximum sensitivity corresponding to the strength of the Earth's natural field. Theses feature could help the bird not only determine in which direction it was heading, but also be able to reveal a kind of GPS location of its approximate position.” [Quoted from scienceworldreport.com]

absolute zero is absolute, but can look like it isn’t

In the mid 18th century, Lord Kelvin defined temperature as nothing could be colder than absolute zero. Physicists later would describe absolute zero as corresponding to a theoretical state where particles do not move, they have absolutely no energy, while at higher energies particles exhibit higher average energies. No temperatures are possible below absolute zero, 0°K [-273°C]. There are no negative °K.

But this was shown to be apparently not be true in some circumstances.

“It is possible to create negative temperatures. It was actually first done in 1951. But it’s not what it sounds like – these temperatures aren’t colder than absolute zero. For instance, you can’t keep cooling something down to make its temperature drop below absolute zero. In fact, as I’ll try to explain, objects at a negative temperature actually behave as if they’re HOTTER than objects that are at any positive temperature.”

Graduate physics student Aatish Bhatia continues:

“...you first need to engineer a system that has an upper limit to its energy. This is a very rare thing – normal, everyday stuff that we interact with has kinetic energy of motion, and there is no upper bound to how much kinetic energy it can have. Systems with an upper bound in energy don’t want to be in that highest energy state. ...these systems have low entropy in (i.e. low probability of being in) their high energy state. You have to experimentally ‘trick’ the system into getting here. This was first done in an ingenious experiment by Purcell and Pound in 1951, where they managed to trick the spins of nuclei in a crystal of Lithium Fluoride into entering just such an unlikely high energy state. In that experiment, they maintained a negative temperature for a few minutes. Since then, negative temperatures have been realized in many experiments, and most recently established in a completely different realm, of ultracold atoms of a quantum gas trapped in a laser.”
[Quoted from empiricalzeal.com]

Here is the abstract from the paper on ultracold atoms just published in Science:

Absolute temperature is usually bound to be positive. Under special conditions, however, negative temperatures—in which high-energy states are more occupied than low-energy states—are also possible. Such states have been demonstrated in localized systems with finite, discrete spectra. [...] Negative temperatures imply negative pressures and open up new parameter regimes for cold atoms, enabling fundamentally new many-body states.
[Negative Absolute Temperature for Motional Degrees of Freedom by Braun et al, Science 4 January 2013: Vol. 339 no. 6115 pp. 52-55. Note, Science has a paywall.]

the web address for the article above is
https://www.abelard.org/news/science082012.php#absolute_zero_060113

photographing molecules and bonds

   
fullerene, or buckyball, carbon bonds, that on the right shows bond distortions. Image credit: IBM

“Graphene devices are being studied as potential replacements for existing technologies used for microchips. Graphene is predicted to eventually have applications in high-bandwidth wireless communications and electronic displays. Researchers at IBM have been able to image the bond order and length of individual carbon-carbon bonds in C60. C60 is also known as a buckyball thanks to its football shape and to planar polycyclic aromatic hydrocarbons resembling small flakes of graphene.

“IBM notes that individual bonds between carbon atoms in these molecules differ slightly and subtly in length and strength. Those subtle differences in the length and strength of bonds between carbon atoms are responsible for the important chemical, electronic, and optical properties of such molecules. IBM’s breakthrough marks the first time the differences in those individual bonds were detected in both individual molecules and individual bonds.”

the web address for the article above is
https://www.abelard.org/news/science082012.php#molecule_bonds_160912

updated - why richard dawkins is wrong

“ "Would you like to talk about Dawkins?" he continues – and when I say yes, he laughs. "I hesitate to do this because he's such a popular guy, but Dawkins is not a scientist..." ”
—
“Individual selection is responsible for much of what we call sin, while group selection is responsible for the greater part of virtue," he writes in one of the book's bluntest passages. "Together they have created the conflict between the poorer and better angels of our nature."

“Critics have attacked this dramatically simplified version of the human condition. But the fiercest argument is about evolution itself. Put simply, the theory of kin selection developed by WD ("Bill") Hamilton in the 1960s and championed by Wilson at the time says that insects such as ants evolved to become altruists because co-operating with their kin helped individuals promote their own genes. It doesn't matter if you give up the opportunity to reproduce yourself, goes the theory, so long as close relatives spread your genes instead.”

“It was therefore inevitable that the genetic code prescribing social behaviour of modern humans is a chimera. One part prescribes traits that favour success of individuals within the group. The other part prescribes the traits that favour group success in competition with other groups.” [p.54]

This book is divided into three sections. I have read the first. It is written on an elementary level, but is clear, with some added ranting and immature speculation. Fortunately, those sections are short!

The second section is on insect behaviour, this is more interesting as he is expert in that area, and the third section is pretty well redundant.

The book is generally sound, but very badly written. It is often too vague, and it could have done with a seasoning of maths. And from time to time, the author goes on a mystical rave, which can be tiresome.

I award Three GoldenYaks and be it on your own head.

the web address for the article above is
https://www.abelard.org/news/science082012.php#dawkins_wrong_190812

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