Life originated in “a warm little pond,” Charles Darwin wrote to Joseph J. Hooker, the founder of geographical botany within Darwin’s circle of colleagues. How, where, and when the first species got started, however, completely escaped Darwin.
In contemplating the origin of life dilemma, Darwin noted in his autobiography –
“The mystery of the beginning of all things is insoluble by us, and I, for one, must be content to remain an agnostic.”
Scientists last week proposed new evolutionary relationships among all 9,993 of the world’s known living bird species. In a letter published in the prestigious Nature journal, scientists reported on the use of DNA-sequence data to create a radiating phylogenetic tree, a revolutionary new bird tree of life (pictured left).
Walter Jetz (pictured right), an evolutionary biologist at Yale University in New Haven, Connecticut, was the leading author of the letter entitled “The global diversity of birds in space and time.” In an interview with science writer Virginia Gewin for Nature News, Jetz explains –
“This is the first dated tree of life for a class of species this size to be put on a global map.”
As the novelty generating the flight of birds, the feather, the most complex integumentary structure found in vertebrates, has long intrigued and fascinated naturalists.
Since Charles Darwin published The Origin of Species in 1859, however, the origin of the feather emerged as a contentious issue. The newfound association between feathers and dinosaurs has only intensified the problem.
The junk DNA theory was introduced in 1972 by evolutionary geneticist Susumu Ohno in the paper entitled “So Much ‘Junk’ in Our Genome.”
The junk comprises sections in the genome with no discernible function, it was thought. Previously, in 1970, Ohno gained notoriety for his gene duplication-driven theory presented in his book Evolution by Gene Duplication.
“Human evolution is the lengthy process of change by which people originated from apelike ancestors,” explains the Smithsonian Institute exhibit (pictured left) entitled “Introduction to Human Evolution.” Continuing their explanation –
“Scientific evidence shows that the physical and behavioral traits shared by all people originated from apelike ancestors and evolved over a period of approximately six million years.”
Exploring human evolution via DNA was essential for twentieth-century evolution scientists. Charles Darwin, however, in The Origin of Species, never used the terms genetics, genetic, and genes until 1872, following the publication of the pea plant inheritance report of Gregor Mendel in 1866.
In his sixth edition, Darwin used the term “genetic” twice, but only to express a genealogical idea, not as a molecular term. In the words of American evolutionary biologist Richard Lewontin,
“Darwin knew nothing about genes.”
Deciphering evidence for sea star evolution has long intrigued biologists. To explore speciation between two similar-looking sea stars, Jonathan Puritz (pictured below) of the Institute of Marine Biology at The University of Hawaii coordinated a research team to correlate the genetic and geographic differences between two Coral Sea species.
The team’s report, entitled “Extraordinarily rapid life-history divergence between Cryptasterina sea star species,” was published last week in the Proceedings of the Royal Society.
Clues from fossilized mating turtles (pictured left) point to an enormous and sudden geological event. In last week’s edition of Biology Letters published by the Royal Society, Walter Joyce (pictured right) of Geosciences at the University of Tübingen in Germany.
The letter, entitled “Caught in the act: the first record of copulating fossil vertebrates,” updates information on the fossilized turtles discovered 30 years ago.
ABC News, BBC News, National Geographic, New York Daily News, MSNBC, FOX News, and Nature and Science journals featured the story, an unprecedented finding.
The search for an explanation for the origin of life started long before the publication of Charles Darwin’s Origin of Species in 1859. The first naturalistic theory of life arising from non-life, known as spontaneous generation, is attributable to Aristotle and ancient Greek philosophy.
Darwin rejected the Genesis account of creation written by Moses. Lingering doubts over the origins of life, however, forced Darwin to reject atheism and embrace agnosticism –
“The mystery of the beginning of all things is insoluble by us, and I, for one, must be content to remain an Agnostic.”
Andrew J. Wendruff and Mark V. H. Wilson of the University of Alberta added a new dimension to the ongoing coelacanth saga this week in the paper “A fork-tailed coelacanth, Rebellatrix divaricerca,” published in the Journal of Vertebrate Paleontology.
In the paper, Wendruff and Wilson present a newly discovered coelacanth species found surprisingly on the rocky slopes of the Canadian Rockies, British Columbia.
The species named Rebellatrix divaricerca means “rebel coelacanth (with a) forked tail.” Far different from today’s Indian Ocean coelacanths, these ancient rebel fast-swimming predators further undermine attempts to develop a cohesive coelacanth evolution saga.
