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The synthesis is arguably the second most important historical event in evolutionary biology after the publication of the 'Origin of Species' As its name indicates the Modern Synthesis is not a dramatic new discovery. Like the 'Origin' itself it ties together many disparate aspects of biology and unifies them. Unlike the 'Origin' the Modern Synthesis was not the work of one person nor was there a single unifying event.

So what the heck was it? In the previous diary we discussed how the theoretical work of R.A. Fisher, Sewall Wright, and J.B.S. Haldane in the 1920s demonstrated how various evolutionary forces could act on the frequencies of alleles (particular versions of genes) in populations and cause those frequencies to change (i.e. evolution). At the time very few biologists had the mathematical background to appreciate these papers.

The synthesis involved

a) the dissemination of Fisher, Wright, and Haldane's findings into the broader biological community.

b) the realization that the disparate evolutionary phenomena studied in different subdisciplines could be unified by these findings

c) the realization that evolution over the short term (microevolution) and over the long term (macroevolution) had the same underlying processes.

...The results of geneticists were not widely appreciated by other biologists for most of the first half of the 20th century. Richard Lewontin, probably the most influential post-synthesis population geneticist, describes being told as an undergraduate that genetics was a passing fad. This was in 1951!

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The researchers caution that the warming applies to this particular region over a time when wind farms were expanding rapidly. The results are not directly applicable for other regions. They should not be extrapolated over a longer period of time. They also note that the warming is a local effect. It would not contribute to a larger global trend adding to global warming. This is not a situation where large amounts of heat are being generated and released into the atmosphere. What is occurring is the mixing of existing heated air.

science green_energy global_climate_change

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If recent cuts to planetary science weren't drawing blood before, they are now. Because this week a group of scientists reexamined data from the 1976 Viking Landers and announced we had indeed found strong evidence of microbial life on Mars at that time: ...

This is an extraordinary claim, as such it will require extraordinary evidence... Ergo, all eyes are now on NASA's Mars programs and especially the Mars Science Laboratory already en route to the red planet ... But [it] does not have either of the two items that might solve this issue once and for all: a high power microscope or return sample capability.

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The world is close to reaching tipping points that will make it irreversibly hotter, making this decade critical in efforts to contain global warming, scientists warned on Monday.

science global_climate_change

...esearchers have turned to satellite imagery to uncover a vast network of over 14,000 long-overlooked Mesopotamian settlements, spanning 8,000 years of ancient civilization. Their findings represent a monumental step forward for the fields of archeology and anthropology, and suggest that an aerial perspective may hold the key to unlocking the mysteries of humanity's first major settlements.
A significant body of archaeological evidence suggests that the earliest civilizations arose in Mesopotamia, the geographic region that today comprises Iraq, northeast Syria, southeast Turkey and southwest Iran. The size and distribution of these settlements throughout the Mesopotamian landscape, however, has long remained something of a mystery. ...

science archaeology

To achieve their extraordinary coordination, starling flocks in flight behave mathematically like metals becoming magnetized, researchers say.

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Signature whistles were first discovered by Melba and David Caldwell in the 1960s, but we still know relatively little about how they’re used. We know that bottlenose dolphins develop their signatures when they’re a few months old, possibly modelling them on those of their mothers. They can go unchanged for decades, although males will sometimes change their whistles to resemble that of a new ally.

The signature whistles seem to act like badges of identity. One dolphin can learn information about another by listening to its whistle. But they’re not entirely like human names. For a start, they’re invented, rather than bestowed.

[Um. Methinks I detect a whiff of cultural bias. -L]

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One of the fun things about science is the many times you scoff at something being impossible, like say, lasers being able to erase metal from x-ray scans, and end up being a fool who was completely wrong about everything. ...

In an electric field, water molecules align themselves so that their positive ends face one way and their negative ends face the other. That directional quality can actually stay in the water as it freezes, so a frozen icicle can have one end with only the positive hydrogen ends of the water sticking outwards and one end with only the negative oxygen ends sticking outwards.

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Superconductivity is a rare physical state in which matter is able to conduct electricity -- maintain a flow of electrons -- without any resistance. This phenomenon can only be found in certain materials at low temperatures, or can be induced under chemical and high external pressure conditions. Research to create superconductors at higher temperatures has been ongoing for two decades with the promise of significant impact on electrical transmission. New work from a team including Carnegie's Xiao-Jia Chen and Ho-kwang "Dave" Mao demonstrates unexpected superconductivity in a type of compounds called iron selenium chalcogenides.

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Biological research is increasingly debunking the view of humanity as competitive, aggressive and brutish.

"Humans have a lot of pro-social tendencies," Frans de Waal, a biologist at Emory University in Atlanta, told the annual meeting of the American Association for the Advancement of Science on Monday.

...Until just 12 years ago, the common view among scientists was that humans were "nasty" at the core but had developed a veneer of morality ...

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It may look like an ordinary USB memory stick, but a little gadget that can sequence DNA while plugged into your laptop could have far-reaching effects on medicine and genetic research.

The UK firm Oxford Nanopore built the device, called MinION, and claims it can sequence simple genomes – like those of some viruses and bacteria – in a matter of seconds. More complex genomes would take longer, but MinION could also be useful for obtaining quick results in sequencing DNA from cells in a biopsy to look for cancer...

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The speed someone walks may predict the likelihood of developing dementia later in life, according to researchers in the US.

They also told a conference that grip strength in middle-age was linked to the chance of a stroke.

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The time of the day could be an important factor in the risk of getting an infection, according to researchers in the US.

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Eighty-seven years after it was written, ABC of Relativity still stands as one of the most intelligible introductions to Albert Einstein’s theories. Russell wrote the book in 1925 as a companion to his earlier volume, ABC of Atoms. The project of writing books for a general readership was born of necessity. Russell had no academic appointment, and needed the money. But as Peter Clark explains in his introduction to the Routledge fifth edition to ABC of Relativity, the early 1920s were also a time when Russell was becoming increasingly preoccupied with social and political issues. He believed that many of the social ills of the period, including the rise of nationalism, were consequences of a widespread and entrenched irrationality, born of ignorance and a lack of education.

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In the previous diary we saw how in the early 19th century the fossil record and other geological evidence supported both the idea that the earth was ancient and that life on earth had changed over time. A number of scholars had proposed biological evolution and some had even proposed natural selection. So then why is Charles Darwin (1809-1882) celebrated above all other biologists and why is the publication of his work, 'On the Origin of Species' considered the most momentous event in the history of biology?

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