700,000-Year-Old Horse Becomes Oldest Creature With Sequenced Genome - ScienceNOW

700,000-Year-Old Horse Becomes Oldest Creature With Sequenced Genome

by Gisela Telis on 26 June 2013, 2:45 PM 

Scientists have sequenced the oldest genome to date—and shaken up the horse family tree in the process. Ancient DNA derived from a horse fossil that's between 560,000 and 780,000 years old suggests that all living equids—members of the family that includes horses, donkeys, and zebras—shared a common ancestor that lived at least 4 million years ago, approximately 2 million years earlier than most previous estimates. The discovery offers new insights into equine evolution and raises the prospect of recovering and exploring older DNA than previously thought possible.

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Two Mutations Triggered an Evolutionary Leap 500 Million Years Ago

June 24, 2013 — Evolution, it seems, sometimes jumps instead of crawls. A research team led by a University of Chicago scientist has discovered two key mutations that sparked a hormonal revolution 500 million years ago.

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What caused the Cambrian explosion? « Why Evolution Is True

What caused the Cambrian explosion?

The “Cambrian explosion” marked the rapid appearance of many animal phyla that persist today, and began about 570 million years ago (mya). Life itself appeared in the fossil record as simple cyanobacteria—”blue green algae”—about 3.6 billion years ago (bya); the first “true” cell with a nucleus probably arose about 2 bya; and the first multicellular organism between 1 and 2 bya.

The “explosion”, contrary to some creationists, wasn’t instantaneous, so it couldn’t have marked a single creation “event” at one time. Rather, the origination of many (but not all) modern phyla occurred between 570 and 540 mya. So the “explosion” took at least thirty million years.

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A Transitional Turtle | Eye on the ICR

A Transitional Turtle

25JUN

Turtles: how did they evolve?

Turtles (a group which includes within it tortoises) are most famous for their shells, which are made of their fused ribs. No other animal has a shell constructed in this manner, and it is a feature that all turtles share. The turtle evolution question, therefore, is somewhat synonymous with how turtle shells evolved. It’s also a case where creationists might reasonably ask “where are the transitional forms” – how do you get to shell from no shell? Unfortunately for them, fossils that fit the bill do exist. In 2009, for example, fossils of Odontochelys were discovered in China. This turtle had a complete plastron, the bottom of the shell, but instead of the upper part (the carapace) it merely had broadened rib bones. That sounds like a transitional form to me.

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From Tiny to Massive: Mammal Size Evolution Explained

June 25, 2013 — Scientists have added another piece to the evolutionary puzzle to explain why certain mammal families evolved to be very large, while others remained tiny.

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