December 31, 1514, O.S. (a Sunday)

On this date at 5:45 AM, the physician and anatomist Andreas Vesalius was born in Brussels, Belgium (at that time part of the Holy Roman Empire). Vesalius sought to understand the mechanisms of the natural world through careful observation, no longer relying on texts by ancient authorities. He is often referred to as the founder of modern human anatomy.

Vesalius studied in Louvain and Paris before earning a doctorate in medicine at the University of Padua in 1537. Appointed there as a lecturer in surgery at the age of twenty-three, he quickly consolidated his reputation as both a teacher and an anatomist. Perhaps his most famous accomplishment was the publication in 1543 of De humani corporis fabrica libri septem (Seven Books on the Construction of the Human Body), or the Fabrica, a text that contained the first accurate illustrations of internal human anatomy. His book overthrew many of the previously uncontested doctrines of the second-century anatomist Galen, and caused a storm of criticism from other anatomists. It was revolutionary, as he was among the first to perform thorough cadaver dissections himself. He showed that Galen’s anatomy was merely an attempt to apply animal structure to the human body, and was not based on any direct knowledge of human anatomy. In the preface of Fabrica, dated August 1, 1542, Vesalius wrote:

To this man they have all so entrusted their faith that no doctor has been found who believes he has ever discovered even the slightest error in all the anatomical volumes of Galen, much less that such a discovery is possible: even though (notwithstanding that Galen often corrects himself, that more than once after learning better he points out in some books a careless error he has made in others, and that he often contradicts himself) – even though it is just now known to us from the reborn art of dissection, from the careful reading of Galen’s books, and from the welcome restoration of many portions thereof, that he himself never dissected a human body, but in fact was deceived by his monkeys (granted a couple of dried-up human cadavers came his way) and often wrongly disputed ancient doctors who had trained themselves in human dissections. In fact, you will find many things in Galen which he misunderstood even in monkeys, not to mention the most astonishing fact that among the many and infinite differences between the organs of the human body and the monkey Galen noticed only those in the fingers and the flexion of the knee; he would no doubt have missed these as well, had they not been obvious to him without dissecting a human.

Vesalius’s discovery of the important differences between species also helped usher in the science of comparative anatomy, in which researchers studied animals to find their similarities and differences. In the process, they gradually began to recognize humans as being one species among many, with a few unique traits but many others shared in common with other animals. Some 300 years after Vesalius first shook off the blind obedience to Galen, Darwin used that vast stock of anatomical knowledge to build his theory of evolution.

December 30, 1818 (a Wednesday)

On this date,  Samuel Latham Mitchill appeared in the packed chambers of the Mayor’s Court in New York City Hall as the star witness in the case of James Maurice v. Samuel Judd, a dispute arising under a New York State statute that obliged purveyors of “fish oils” to ensure that their casks had been gauged, inspected, and certified.

December 28, 1894 (a Friday)

On this date, the American vertebrate paleontologist and comparative anatomist Alfred Sherwood Romer was born. The Society of Vertebrate Paleontology, which Romer helped establish, says that he “was the leading contributor to the discipline of vertebrate paleontology throughout the twentieth century…Romer’s major contributions were in the areas of the ancestry of vertebrates, Paleozoic tetrapods, and the antecedents of mammals.” Perhaps Romer’s most notable gift to scientific posterity were his three seminal works: Osteology of the Reptiles (1956), Vertebrate Paleontology (1966), and The Vertebrate Body (1977) – immortal tomes which still adorn the shelves of any self-respecting student of vertebrate paleontology and evolution.

December 27, 1831 (a Tuesday)

On this date, HMS Beagle with Charles Darwin on board set sail from Plymouth, England, beginning its epic voyage with a crew of 73 men under clear skies and a good wind. Darwin became sea-sick almost immediately. Later, he wrote in his diary:

A beautiful day, accompanied by the long wished for E wind.—Weighed anchor at 11 o’clock & with difficulty tacked out.—The Commissioner Capt Ross sailed with us in his Yatch.—The Capt, Sullivan & myself took a farewell luncheon on mutton chops & champagne, which may I hope excuse the total absence of sentiment which I experienced on leaving England.—We joined the Beagle about 2 o’clock outside the Breakwater,—& immediately with every sail filled by a light breeze we scudded away at the rate of 7 or 8 knots an hour.—I was not sick that evening but went to bed early.

December 27, 1822 (a Friday)

On this date, the chemist and microbiologist Louis Pasteur was born in Dole in the Jura region of France.

From the time of the ancient Romans, through the Middle Ages, and until the late nineteenth century, it was generally accepted that some life forms arose spontaneously from nonliving matter. Such “spontaneous generation” appeared to occur primarily in decaying matter. For example, a seventeenth century recipe for the spontaneous production of mice required placing sweaty underwear and husks of wheat in an open-mouthed jar, then waiting for about 21 days, during which time it was alleged that the sweat from the underwear would penetrate the husks of wheat, changing them into mice. Likewise, the spontaneous generation hypothesis was proposed by scientists to explain the origin of the “animalcules” observed by Antoni van Leeuwenhoek in his magnifying lenses and had received wide acceptance all over Europe. Although such a concept may seem laughable today, it was consistent with the other widely held cultural and religious beliefs of the time.

It wasn’t until Louis Pasteur that this fallacy was finally disproved. In 1859, the French Academy of Science offered the Alhumbert Prize of 2500 francs to whoever could shed “new light on the question of so-called spontaneous generation”. Young Pasteur’s award winning experiment was a clever variation of earlier experiments performed by John Needham (1713-1781) and Lazzaro Spallanzani (1729-1799). Pasteur filled a long necked flask with meat broth. He then heated the glass neck and bent it into an “S” shape. Air could reach the broth, but gravity acted to trap airborne microorganisms in the curve of the neck. He then boiled the broth. After a time, no microorganisms had formed in the broth. When the flask was tipped so that the broth reached the microorganisms trapped in the neck, the broth quickly became cloudy with microscopic life.

Thus, Pasteur disproved spontaneous generation. Furthermore, Pasteur proved that some microorganisms are airborne. “There is no known circumstance in which it can be confirmed that microscopic beings came into the world without germs, without parents similar to themselves,” he concluded in 1864. His experiment also supported germ theory. Germ theory states that specific microscopic organisms are the cause of specific diseases. While Pasteur was not the first to propose germ theory (Girolamo Fracastoro, Agostino Bassi, Friedrich Henle and others had suggested it earlier), he developed it and conducted other experiments that clearly indicated its correctness, thereby managing to convince most of Europe it was true.

Despite what creationists and proponents of “intelligent design” may insist, Pasteur’s research on spontaneous generation did not demonstrate the impossibility of life arising in simple form from nonliving matter under conditions vastly different from those today and by means of a long and propitious series of chemical steps/selections. In particular, he did not show that life cannot arise once, and then evolve. Neither Pasteur, nor any other post-Darwin researcher in this field, denied the age of Earth or the fact of evolution. What Louis Pasteur and the others who denied spontaneous generation did demonstrate is that life does not currently spontaneously (i.e., within a matter of weeks) arise in complex form from nonlife in nature.

If it walks like a tax and quacks like a tax…

Written in 1960, the Master Plan for Higher Education in California designed specific regulations for all California institutions of higher education in order to promote student success.

The plan initiated “enrollment fees” instead of tuition to keep costs down and encourage commitment to higher education. In Chapter IX, it noted that:

Tuition is defined generally as student charges for teaching expenses, whereas fees are charges to students, either collectively or individually, for services not directly related to instruction, such as health, special clinical services, job placement, housing, recreation.

In other words, student fees were to be for “auxiliary costs”.

The rules of the plan are especially stringent for junior [community] colleges, which must maintain quality standards because they have to accept everyone. Community colleges offer education through grade fourteen, two years after high school graduation. The standard collegiate courses offered are transferable to higher institutions, including vocational and technical offerings and liberal arts courses.

Although intended originally to be nominal, “enrollment fees” have steadily risen to the point of being a euphemism for tuition. This is evident because the cost of attending community colleges in California is routinely compared with the tuition charged by community colleges in other states.

Furthermore, in practice, fees tend to rise or fall based on whether the state budget is in the red or black, not on whether “auxiliary costs” are going up or down. Thus, you can have the ludicrous situation in which fees are being raised at the same time that state financial support for the community college system is being cut. In effect, the “fees” that are being imposed on students are really taxes – they are being used to balance the state budget. The time to stop this Orwellian “double-speak” is NOW.

December 23, 1924 (a Tuesday)

On this date, Raymond Dart completed his work removing the first fossil skull of Australopithecus from its matrix of rock. Being one of the “missing links” in man’s evolution, Dart had taken exquisite care during 73 days to separate skull and stone, at work in his laboratory in Johannesburg, South Africa. Dart with his students made the find in the Taung limestone works in the Harts Valley of Bechuanaland. When an endocranial cast was found, at first it seemed to be just another primate skull. Then, Dart noticed how amazingly close to human it looked. Dart had discovered the Taung child, who was only three years old at the time of death. He named it Australopithecus africanus. (Australis means “south” and pithecus means “ape”).

December 23, 1810 (a Sunday)

On this date, the English zoologist and chemist Edward Blyth was born in London. Although he was considered one of the leading zoologists in India, and a prominent figure overall in his field, he is best known for his early (1835) recognition of some of the principles of natural selection. Blyth, however, did not see the ramifications of the principle (nor did anyone else), and did little to develop his thoughts any further. Later he became one of the first to embrace Darwinism, and was a vocal supporter for the remainder of his years.

Interestingly, Blyth’s writings had a major influence on Charles Darwin. There can be no doubt of Darwin’s regard for Edward Blyth – in the first chapter of The Origin of Species he wrote:

…Mr Blyth, whose opinion, from his large and varied stores of knowledge, I should value more than that of almost any one…

December 22, 1938 (a Thursday)

On this date, a coelacanth (Latimeria chalumnae) was caught at the mouth of the Chalumna River on the east coast of South Africa. The fish was caught in a shark gill net by Captain Goosen and his crew, who had no idea of the significance of their find. They thought the fish was bizarre enough to alert the local museum in the small South African town of East London.

The director of the East London Museum at the time was Miss Marjorie Courtney-Latimer. She alerted the prominent south African ichthyologist Dr J.L.B. Smith to this amazing discovery. This modern coelacanth was eventually named in honor of Miss Courtney-Latimer.

This coelacanth specimen led to the discovery of the first documented population, off the Comoros Islands, between Africa and Madagascar. For sixty years this was presumed to be the only coelacanth population in existence. However, on July 30, 1998, a coelacanth was caught in a deep-water shark net by local fishers off the volcanic island of Manado Tua in northern Sulawesi, Indonesia, about 10,000 km east of the Western Indian Ocean coelacanth population. In 1999 the Sulawesi coelacanth was described as a new species, Latimeria menadoensis, by Pouyaud, Wirjoatmodjo, Rachmatika, Tjakrawidjaja, Hadiaty and Hadie.

Coelacanths are known from the fossil record dating back over 360 million years, with a peak in abundance about 240 million years ago. Before 1938, they were thought to have become extinct approximately 80 million years ago, when they disappeared from the fossil record, so the discovery of a living coelacanth was very significant. But why are there no coelacanth fossils since the days of the dinosaurs? The explanation seems to be that the coelacanths from the fossil record lived in environments favoring fossilization, whereas modern coelacanths, both in the Comoros and Sulawesi, are found in environments that do not favor fossil formation. They inhabit caves and overhangs in nearly vertical marine reefs, at about 200 m depth, off newly formed volcanic islands.

One of the most interesting features of the coelacanth is that it has paired lobed fins that move like our arms and legs do. At the time of its discovery in 1938, the coelacanths were thought to be the ancestors of the tetrapods (terrestrial animals with four limbs). Although it is now thought that the lungfishes are the closest living relative of tetrapods, the coelacanth may still provide answers to some very interesting evolutionary questions.

December 21, 1889 (a Saturday)

On this date, the American mathematician and biologist Sewell Green Wright was born. He was one of the founders, along with R. A. Fisher and J. B. S. Haldane, of modern theoretical population genetics. He researched the effects of inbreeding and crossbreeding with guinea pigs and, later on, the effects of gene action on inherited characteristics. The synthetic theory of evolution as described by Sewell Wright attempts to explain evolution in terms of changes in gene frequencies.

The classic example which supports this theory is that of the peppered moth in England. The moth can be either dark or light colored. Scientists have determined that body color in the peppered moth is controlled by a single gene with two alleles: the allele for dark body color is dominant and the allele for light body color is recessive. Prior to the industrialization of central England, the light-colored allele was most prevalent. The light-colored moths would hide on the white-barked trees and avoid bird predation. But the pollution generated by the new industries stained the light-colored trees dark. Gradually the light-colored moth was attacked and that allele became much less prevalent. In its place, the dark-colored allele became the most predominant allele because moths that carried that allele could camouflage themselves on the stained trees and avoid being eaten by their bird predators. Clearly the population had evolved to a higher adaptive condition.

Wright is perhaps best known for his concept of genetic drift, formerly known as the “Sewell Wright effect.” Genetic drift results when small populations of a species are isolated and due to pure chance, the few individuals who carry certain relatively rare genes may fail to transmit them. The genes may therefore disappear and their loss may lead to the emergence of new species, although natural selection has played no part in the process. Genetic drift can be summarized as “bad luck, not bad genes.”

December 21, 1767 (a Monday)

On this date, William Paley was ordained as an Anglican priest. He was a prolific author, but his most influential contribution to biological thought was his book Natural Theology: or, Evidences of the Existence and Attributes of the Deity, Collected from the Appearances of Nature, first published in 1802. He introduced one of the most famous metaphors in the philosophy of science, the image of the watchmaker:

. . . when we come to inspect the watch, we perceive. . . that its several parts are framed and put together for a purpose, e.g. that they are so formed and adjusted as to produce motion, and that motion so regulated as to point out the hour of the day; that if the different parts had been differently shaped from what they are, or placed after any other manner or in any other order than that in which they are placed, either no motion at all would have been carried on in the machine, or none which would have answered the use that is now served by it. . . . the inference we think is inevitable, that the watch must have had a maker – that there must have existed, at some time and at some place or other, an artificer or artificers who formed it for the purpose which we find it actually to answer, who comprehended its construction and designed its use.

Natural theology had dominated English thinking for nearly two centuries, Paley’s arguments going back to authors such as John Ray, and have had a long intellectual history, surviving to the present day in many a piece of creationist rhetoric. Although totally discredited in modern science, natural theology was important scientifically because it guided researchers to the fundamental question of how life works. Even today, when scientists discover a new kind of organ or protein, they try to figure out its function.

December 20, 2005 (a Tuesday)

On this date, Kitzmiller et al. v. Dover Area School District was decided.

First, some background information. In October 2004, the Dover [PA] Area School District Board of Directors had decided that “Students will be made aware of gaps/problems in Darwin’s theory and of other theories of evolution including, but not limited to, intelligent design.” In November 2004, they had announced that Dover High School’s ninth-grade biology teachers would read a statement informing students that “Darwin’s Theory . . . is not a fact” and that “intelligent design is an explanation of the origin of life that differs from Darwin’s view.” The statement referred students to the creationist textbook Of Pandas and People to learn “what intelligent design actually involves.” On December 14, 2004, eleven parents had filed suit in the Middle District of Pennsylvania against the District’s Board of Directors. [Interestingly, in January 2005, science teachers refused to read the ID statement; administrators read it themselves.] The trial had begun on September 26, 2005.

The presiding judge, John E. Jones III, was not fooled by the defendants’ denials that they are creationists: “[Intelligent Design] cannot uncouple itself from its creationist, and thus religious, antecedents.” He was especially displeased that board members Buckingham and Bonsell had lied under oath during their depositions: “[T]he inescapable truth is that both Bonsell and Buckingham lied at their January 3, 2005 depositions about their knowledge of the source of the donation for Pandas. . . . This mendacity was a clear and deliberate attempt to hide the source of the donations . . . to further ensure that Dover students received a creationist alternative to Darwin’s theory of evolution [emphasis added].” Presented with the truth about the board’s policy and the ID creationism it promoted, Jones ruled accordingly: “A declaratory judgment is hereby issued in favor of Plaintiffs . . . such that Defendants’ ID Policy violates the Establishment Clause of the First Amendment of the Constitution of the United States and . . . the Constitution of the Commonwealth of Pennsylvania.”

The victory was not just legal; the pro-ID school board was replaced by the voters on November 8, 2005.

December 19, 1944 (a Tuesday)

On this date, the Kenyan physical anthropologist and paleontologist Richard E. Leakey was born. Leakey, second of three sons of noted anthropologists Louis Leakey and Mary Leakey, decided at an early age that he wanted nothing to do with paleoanthropology and started a expedition business. In 1964, he led an expedition to a fossil site which sparked his interest in paleontology. Since then he has been responsible for extensive fossil finds of human ancestral forms in East Africa, including a Homo habilis skull found in 1972, and a Homo erectus skull found in 1975. His discoveries showed that man’s ancestors used tools, which shows intelligence, and lived in eastern Africa at least 3 million years ago – almost doubling the previously accepted age of human origins.

December 18, 1832 (a Tuesday)

HMS Beagle off Tierra del Fuego
(from an original by Raymond A Massey)

On this date, after passing through the straight of Le Maire at Tierra del Fuego, HMS Beagle anchored at Good Success Bay. Here Charles Darwin had his first encounter with savages. He was shocked by the primitive way of life they led but was also fascinated by them. A group of four male Fuegians met the landing party. After an attempt to communicate with the Feugians the party presented them with some bright red cloth and the Feugians immediately became friendly with them. The natives initiated a dialog by patting the crewmen on their chests. Apparently they had the most amazing ability to mimic the crew’s gestures and even the words they spoke, often repeating whole English sentences back to them. Darwin was bewildered by all this.

December 18, 1912 (a Wednesday)

Working at Piltdown.

 

 

On this date, the discovery of the skull known as Piltdown man, the first important fossil human skull ever to be unearthed in England, was announced at a meeting of the Geological Society of Great Britain. Charles Dawson, steward of Barkham Manor, an attorney, and secretary to the Sussex Archaeological Society, and Arthur Smith Woodward, keeper of geology at the British Museum, announced their remarkable find had been made at Piltdown Common. The specimen, known as Piltdown man, occupied an honored place in the catalogues of fossil hominids for the next 40 years. But in 1953, thanks to some rigorous scholarly detective work, Piltdown man was revealed to be nothing more than a forgery, manufactured from modern human and animal remains.

December 16, 1859 (a Friday)

On this date, the American botanist Douglas Houghton Campbell was born. He was an expert on the anatomical structure and life cycles of mosses, ferns and liverworts. Throughout his entire life, Campbell was interested in the evolution of vascular plants, which he thought occurred on land from primitive mosses. He also studied the modern geographic distribution of plants.

At a time before it was generally accepted, Campbell thought Wegener’s theory of continental drift (proposed in 1912) was plausible. Campbell recognized that a primordial supercontinent, Gondwana, splitting into smaller land masses that drifted apart would resolve many of the puzzling facts in geographical distribution, both of animals and plants:

Acceptance of the recent hypothesis of Du Toit, that there were two primordial continents, Laurasia in the Northern Hemisphere and Gondwana in the South, and from these primary continents, the existing continents were separated and shifted to their present positions, would, if true, remove most of the difficulties in explaining the present distribution of many existing plant families.

References:

• Douglas Houghton Campbell, “Relations of the temperate floras of North and South America,” Proceedings of the California Academy of Sciences 25, 4th ser. (1944): 139-146.

December 15, 1869 (a Wednesday)

On this date, the American geologist Joseph Barrell was born. Barrell was professor of structural geology at Yale University from 1908 until his death in 1919. He proposed that sedimentary rocks were produced not only by marine sedimentation but also by the action of rivers, winds, and ice (continental sedimentation). He also proposed (1916) that the bright red color of many Devonian rocks meant that the rocks had been baked dry, like bricks, in arid conditions. [Barrell had been only half right; red rocks do sometimes form in droughts, but they form in moist tropical soils as well.] He, and subsequently the great American paleontologist Alfred Sherwood Romer, speculated that droughts had caused lungfish to evolve into air-breathing land vertebrates, including tetrapods. According to this hypothesis, as the ponds dried, the fish had to adapt to life on land and so evolved features that enabled them to hop from pond to pond. [However, evidence discovered more recently suggests that the fish-to-tetrapod transition likely happened not in creatures that were adapting to land but in creatures living in water. In fact, everything special about tetrapods – limbs, digits, ribs, neck, and so on – might well have evolved in water, not on land.]

At a meeting of the Geological Society of America held in Albany, New York, in 1916 Barrell presented a paper on “Rhythms and the measurement of geologic time” that was later published in full in the Society’s Bulletin in 1917. The article became an instant classic in geology. Barrell argued that geological processes vary in intensity in a cyclical rather than a uniform fashion. Thus, current rates of geological change could not, as uniformitarians claim, be a reliable guide to the past. He suggested that the new radiometric dates should be used to interpret the sedimentological record. Thus, he accepted an age for the Earth of a few billion years at a time when many geologists still preferred an age of 100 million years.

References:

• Joseph Barrell, “Rhythms and the measurements of geologic time,” Geol. Soc. America Bull. 28 (1917): 745-904.
• Patrick Wyse Jackson, The Chronologers’ Quest: The Search for the Age of the Earth (Cambridge, UK: Cambridge University Press, 2006) 195-6.

December 14, 1914 (a Monday)

On this date, the American molecular biologist Sol Spiegelman was born. He developed the technique of nucleic acid hybridization, which helped to lay the foundation for advances in recombinant DNA technology. He is also given credit for an experiment that produced a self-reproducing RNA chain of only 218 nucleotides, which was nick-named Spiegelman’s Monster.

References:

• D.L. Kacian, D.R. Mills, F.R. Kramer, and S. Spiegelman, “A replicating RNA molecule suitable for a detailed analysis of extracellular evolution and replication,” Proceedings of the National Academy of Sciences U.S.A. 69(10): 3038–3042 (Oct. 1972).
• D.R. Mills, R.L. Peterson, and S. Spiegelman, “An extracellular Darwinian experiment with a self-duplicating nucleic acid molecule,” Proceedings of the National Academy of Sciences U.S.A. 58(1): 217-224 (July 1967).

Humans are still evolving – and it’s happening faster than ever!

Very significant research came to my attention yesterday. A study being published in the Proceedings of the National Academy of Sciences shows that humans have evolved in the past 5,000 years up to 100 times more quickly than at any time since their split from the ancestors of modern chimpanzees 6 million years ago.

The study’s principal investigator, anthropologist Dr. John Hawks, was quoted as saying that “The widespread assumption that human evolution has slowed down because it’s easier to live and we’ve conquered nature is absolutely not true. We didn’t conquer nature, we changed it in ways that created new selection pressures on us.” The surge in global population had led to faster evolution since more mutations occur, the researchers said. They think that in the future, the tendency to start families later in life will drive evolution. “People are having problems with infertility, so any kind of genetic variation that increases the success of later fertility will be selected for,” said Hawks.

Jon Stewart stands up for marriage equality.

Religion is far more of a choice than homosexuality… Gay people don’t choose to be gay. At what age did you choose not to be gay?

— Jon Stewart, interviewing Gov. Mike Huckabee on “The Daily Show”

The passage of Prop 8 in California has catalyzed a national discussion of same-sex marriage. And Jon Stewart’s discussion with Mike Huckabee — a prominent social conservative and likely 2012 presidential candidate — may become one of the more significant developments in the ongoing debate over the fundamental right to marriage.