One of the first conditions of happiness is that the link between Man and Nature shall not be broken
Before the chemicals were banned in the United States in 1979, polychlorinated biphenyls, or PCBs, were widely used in the manufacture of electrical devices because they can withstand extremely high temperatures.
“PCBs are changing behavior in subtle but important ways that we’re only beginning to recognize,” says lead author Sara DeLeon. “The Black-capped Chickadees and Song Sparrows we studied ingest PCBs when they eat contaminated insects. The chemicals appear to mimic hormones and interfere with development in the part of the bird’s brain that governs song and song structure.”
Key among the findings is that song disruption is tied to specific types of PCBs—there are 209 variations, differentiated by the positioning and number of chlorine atoms. DeLeon tested 41 of these variations to isolate their effects.
DeLeon chose five study sites in New York State, including two along the Hudson River that were heavily polluted by PCBs dumped illegally from 1947 to 1977. The other sites were not known to have PCB contamination and tests at an Adirondack Mountains site eliminated mercury as a factor in song changes. At each site she collected and tested blood samples from males of the two bird species, recorded their songs over several field seasons, and analyzed those songs.
“The songs of Black-capped Chickadees and Song Sparrows are very well studied,” DeLeon says. “For example, we know that it’s normal for there to be very, very little variation in the way all Black-capped Chickadees deliver their fee-bee song and the interval between the two notes.
We found the greatest variation among birds in areas with higher levels of certain types of PCBs—their songs just were not coming out right. Since dominant males produce the most consistent songs, this variation could have important biological consequences.”
The next logical step, Dhondt notes, would be to use this method to study low-level PCB effects elsewhere to learn how the pollutants are being spread through ecosystems and the effects they could be having.
Other co-authors include research associate Ralph S. Hames; assistant professor of ecology and evolutionary biology André Kessler; and Timothy DeVoogd, professor of psychology, all from Cornell.
Joseph Decker (1853 – 1924)
Johann Friedrich Wilhelm Herbst (1743-1807) was a German naturalist and entomologist, and a theologian and chaplain for the Prussian army.
Versuch einer Naturgeschichte der Krabben und Krebse’ (An attempt at The Natural History of Crabs and Lobsters)
was possibly the first comprehensive work on the crustaceans and definitely included descriptions and illustrations of previously unknown species.
It was released in instalments between about 1782 and the mid-1790s. There were three volumes of text and an atlas consisting of more than sixty hand-coloured engravings. Various editions were issued, some coloured, some not and some coloured later.
It is still regarded as a primary source in the field.
Author: Dr. Tony Phillips
July 24, 2014: The Universe is a big place, full of unknowns. Astronomers using NASA’s Chandra X-ray Observatory have just catalogued a new one.
Together with a team of more than a half-dozen colleagues, Esra Bulbul, of the Harvard Center for Astrophysics, has been using Chandra to explore the Perseus Cluster, a swarm of galaxies approximately 250 million light years from Earth. Imagine a cloud of gas in which each atom is a whole galaxy—that’s a bit what the Perseus cluster is like. It is one of the most massive known objects in the Universe.
The cluster itself is immersed in an enormous ‘atmosphere’ of superheated plasma—and it is there that the mystery resides
“A line appeared at 3.56 keV (kilo-electron volts) which does not correspond to any known atomic transition. It was a great surprise.”
The spectral line appears not to come from any known type of matter, which shifts suspicion to the unknown: dark matter.
The menagerie of dark matter candidates that might produce this kind of line include axions, sterile neutrinos, and “moduli dark matter” that may result from the curling up of extra dimensions in string theory.
“I couldn’t believe my eyes,” says “What we found, at first glance, could not be explained by known physics.”
Solving the mystery could require a whole new observatory. In 2015, the Japanese space agency is planning to launch an advanced X-ray telescope called “Astro-H.” It has a new type of X-ray detector, developed collaboratively by NASA and University of Wisconsin scientists, which will be able to measure the mystery line with more precision than currently possible.
“Maybe then,” says Bulbul, “we’ll get to the bottom of this.”
In 2003 a team of astronomers led by Dr. Andrew Fabian at Cambridge University discovered one of the deepest notes ever detected, a B♭.
No human will actually hear the note, because its time period between oscillations is 9.6 million years, which is 57 octaves below the keys in the middle of a piano.
The stream of debris is called the Perseid cloud. It stretches along the orbit of the comet Swift–Tuttle and consists of particles ejected by the comet as it travels on its 133-year orbit.
Most of the particles have been part of the cloud for around a thousand years.
However, there is also a relatively young filament of dust in the stream that was pulled off the comet in 1865, which can give an early mini-peak the day before the maximum shower.
The earliest information on this meteor shower is found in Chinese annals in A.D. 36. However, credit for recognising the shower’s annual appearance is given to Adolphe Quetelet, who reported in 1835 that there was a shower emanating from the constellation Perseus. Some Catholics refer to the Perseids as the “tears of Saint Lawrence”, since 10 August is the date of that saint’s martyrdom.
The shower is visible from mid-July each year, with the peak in activity between 9 and 14 August, depending on the particular location of the stream. During the peak, the rate of meteors reaches 60 or more per hour. They can be seen all across the sky; but, because of the path of Swift-Tuttle’s orbit, Perseids are primarily visible in the Northern Hemisphere. As with many meteor showers, the visible rate is greatest in the pre-dawn hours, since the side of the Earth nearest to turning into the sun scoops up more meteors as the Earth moves through space. Most Perseids disappear while at heights above 80 kilometres (50 mi)
The Great Fireball of 1783
In the summer of 1783 the Montgolfier brothers flew the first successful hot-air balloon at Annonay in France, creating a craze for ballooning which swept Parisian society, and Henry Cavendish and Joseph Priestley continued their independent experiments on ‘inflammable air’ [hydrogen] and the chemical composition of water.
Sir Joseph Banks, President of the Royal Society for over 41 years, was summering in Lincolnshire while Charles Blagden kept him apprised of scientific goings-on, opened Banks’s mail for him, and marshalled the traffic at Banks’s house at 32 Soho Square – a continual back-and-forth flow of books, drawings, journals, newspapers, plant specimens and people
That same summer a large meteor was seen over England on the night of August 18th, passing rapidly over Scotland and travelling down the east coast of England – it was seen at Lincolnshire, where it appeared to break up, but the core continued, still blazing, more or less on its former trajectory– and at Ramsgate. It was also seen from Brussels and France; and there was an unconfirmed sighting as far south as Rome. Blagden and Banks between them gathered reports of the event from across Britain and the Continent to attempt to estimate the meteor’s size, altitude, and speed; it was visible for a little under a minute, its altitude was estimated variously between 50 and 60 miles, it appeared about as large as the Moon’s disc (Blagden reckoned its diameter at roughly half a mile) and its speed was calculated at 20 miles per second.
These calculations of the meteor’s altitude and speed are remarkably plausible – and if Blagden’s estimate of its size is even marginally accurate then humanity can breathe a two-hundred-year’s delayed sigh of relief at its close shave. Blagden didn’t see it like that, because he didn’t think meteors were physical bodies but electrical phenomena in the upper atmosphere.
When he heard that the Astronomer Royal, Nevill Maskelyne, was sending out queries of his own for an investigation of the comet, he wrote scoffingly to Banks:
‘I hear many years ago Professor [John] Winthrop, of Cambridge [Harvard] in new England, sent a paper to the R.S. containing a circumstantial theory of meteors as bodies revolving in very excentric elipses round our earth, & producing light by their effect upon our atmosphere. This paper it was not thought proper to print; but most likely [Sir John] Pringle took his ideas from it, which Maskelyne is now going to hash up warm. If every falling star be such a body, and it seems impossible to draw a line of distinction between them & the larger meteors, we are in high luck indeed that some of them, out of such an immense number, do not now & then miss their way, or get entangled in our atmosphere, and give us a smack. That this good world may be preserved from such misfortunes is the hearty wish of
Blagden argued in his published paper that it was precisely because meteors were seen so frequently, yet never felt actually to hit, that they weren’t orbiting bodies like comets. His crowd-sourced data was remarkably reliable; and from his description of the meteor you would swear he imagined it as a solid body, but he’s forced away from that conclusion because he can’t find any evidence for the logical endpoint of that line of thought: namely, the meteor’s impact.
Crowd-sourcing observations in this way was an important tool, continues to be important to modern science, and is crucial to the history of science.
Blagden’s dismissive mention of John Winthrop, Hollis Professor of natural philosophy and Astronomy at Harvard is intriguing, in this context. Winthrop’s theory that meteors were of extra-terrestrial origin was substantially correct, and his paper, which the Society hadn’t seen fit to publish at the time, is still in the archives; but he was also responsible for one of the first attempts to treat earthquakes as geological phenomena.
Like meteors and comets, these had largely been regarded prior to the scientific revolution as manifestations of divine wrath or providential omens; Winthrop’s study of the effects of the devastating Lisbon earthquake of 1755, which had also been felt in New England, attempted to measure the damage it caused and to quantify the forces involved, and he published the resulting lecture in Boston as well as sending an account to the Royal Society.
Famous contributing authors to Philosophical Transactions of the Royal Society, which was established in 1665, include Isaac Newton, Michael Faraday, and Charles Darwin.
Sir Joseph Banks took part in the Voyage of HMS Endeavour, exploration of Botany Bay with Captain James Cooke.