News Roundup: Surprise, We're Still Learning New Things

By Dave Thomas

Have you ever noticed how boring Creationism and/or Intelligent Design are? How many times must we endure hackneyed claims like “The Flagellum proves Intelligent Design,” or “The Cambrian Explosion Defies Darwinism” ?

Science, however, is continuously being refined and improved, and new discoveries are the order of the day. Here are a few current stories that have relevance to the creationism-versus-evolution “debate.”

  • Darwin’s Dilemma Resolved: Evolution’s ‘Big Bang’ Explained by Five Times Faster Rates of Evolution
  • Functioning ‘Mechanical Gears’ Seen in Nature for First Time
  • DNA Double Take

More below the fold.

Darwin’s Dilemma Resolved: Evolution’s ‘Big Bang’ Explained by Five Times Faster Rates of Evolution

Sep. 12, 2013 – A new study led by Adelaide researchers has estimated, for the first time, the rates of evolution during the “Cambrian explosion” when most modern animal groups appeared between 540 and 520 million years ago.

The findings, published online today in the journal Current Biology, resolve “Darwin’s dilemma”: the sudden appearance of a plethora of modern animal groups in the fossil record during the early Cambrian period.

“The abrupt appearance of dozens of animal groups during this time is arguably the most important evolutionary event after the origin of life,” says lead author Associate Professor Michael Lee of the University of Adelaide’s School of Earth and Environmental Sciences and the South Australian Museum.

“These seemingly impossibly fast rates of evolution implied by this Cambrian explosion have long been exploited by opponents of evolution. Darwin himself famously considered that this was at odds with the normal evolutionary processes.

“However, because of the notorious imperfection of the ancient fossil record, no-one has been able to accurately measure rates of evolution during this critical interval, often called evolution’s Big Bang.

“In this study we’ve estimated that rates of both morphological and genetic evolution during the Cambrian explosion were five times faster than today – quite rapid, but perfectly consistent with Darwin’s theory of evolution.”

Functioning ‘Mechanical Gears’ Seen in Nature for First Time

Sep. 12, 2013 – Previously believed to be only human-made, a natural example of a functioning gear mechanism has been discovered in a common insect – showing that evolution developed interlocking cogs long before we did.

The juvenile Issus - a plant-hopping insect found in gardens across Europe – has hind-leg joints with curved cog-like strips of opposing ‘teeth’ that intermesh, rotating like mechanical gears to synchronise the animal’s legs when it launches into a jump.

The finding demonstrates that gear mechanisms previously thought to be solely human-made have an evolutionary precedent. Scientists say this is the “first observation of mechanical gearing in a biological structure.”

Finally, Carl Zimmer in the New York Times, on Cells in the Same Organism having Different Genomes! DNA Double Take

From biology class to “C.S.I.,” we are told again and again that our genome is at the heart of our identity. Read the sequences in the chromosomes of a single cell, and learn everything about a person’s genetic information – or, as 23andme, a prominent genetic testing company, says on its Web site, “The more you know about your DNA, the more you know about yourself.”

But scientists are discovering that – to a surprising degree – we contain genetic multitudes. Not long ago, researchers had thought it was rare for the cells in a single healthy person to differ genetically in a significant way. But scientists are finding that it’s quite common for an individual to have multiple genomes. Some people, for example, have groups of cells with mutations that are not found in the rest of the body. Some have genomes that came from other people.

“There have been whispers in the matrix about this for years, even decades, but only in a very hypothetical sense,” said Alexander Urban, a geneticist at Stanford University. Even three years ago, suggesting that there was widespread genetic variation in a single body would have been met with skepticism, he said. “You would have just run against the wall.”

But a series of recent papers by Dr. Urban and others has demonstrated that those whispers were not just hypothetical. The variation in the genomes found in a single person is too large to be ignored. “We now know it’s there,” Dr. Urban said

“Now we’re mapping this new continent.”

Discuss.