Changes

====Australia's 'Toxic Toad'====

====Australia's 'Toxic Toad'====

In one of the most widely publicized cases of unexpected rapid microevolution, Australian Cane Toads defied predictions based on evolutionary theory by experts about how they would react after being introduced to Australia. Within decades they evolved longer legs and heat tolerance, running amok and causing havoc for the wildlife; and instituting a national catastrophe for the continent. {{cquote|The evolutionary processes spawned by the cane toad invasion have occurred in a span of just 70 years. This adds to evidence from the past two decades that populations can adapt quickly when selection pressure is strong. 'We're taught evolution occurs over these very, very long time frames. But in systems like these, it's incredibly fast,' Shine, the study co-author, said.<ref>Roach, John (2006, February 15). "[http://news.nationalgeographic.com/news/2006/02/0215_060215_cane_toads.html Toxic Toads Evolve Longer Legs, Study Says]." ''National Geographic''.</ref>}} {{cquote|'All of a sudden in the last 10 years it changes,' said Skelly. 'They're moving into areas where the physical environment is not like anything in their native range.' That implies that the cane toads have evolved more tolerance for the hotter climates they are now encountering. This is on top of the discovery last year that the toads at the forefront of the invasion had evolved longer legs than those in the interior of their range. The ability of animals to evolve so quickly needs to be factored into invasions, or the dangers of invasive species will likely be underestimated, argue Skelly and his colleagues Mark Urban, Ben Phillips and Richard Shine in an article in the March 28 issue of the Proceedings of the Royal Society-B.<ref>O'Hanlon, Larry (2007, April 2). "[http://news.discovery.com/animals/toxic-cane-toads-evolve-quickly.html Toxic Toads Evolving Quickly]." ''DiscoveryNews''.</ref>}}

In one of the most widely publicized cases of unexpected rapid microevolution, Australian Cane Toads defied predictions based on evolutionary theory by experts about how they would react after being introduced to Australia. Within decades they evolved longer legs and heat tolerance, running amok and causing havoc for the wildlife; and instituting a national catastrophe for the continent. {{cquote|The evolutionary processes spawned by the cane toad invasion have occurred in a span of just 70 years. This adds to evidence from the past two decades that populations can adapt quickly when selection pressure is strong. 'We're taught evolution occurs over these very, very long time frames. But in systems like these, it's incredibly fast,' Shine, the study co-author, said.<ref>Roach, John (2006, February 15). "[http://news.nationalgeographic.com/news/2006/02/0215_060215_cane_toads.html Toxic Toads Evolve Longer Legs, Study Says]." ''National Geographic''.</ref>}} {{cquote|'All of a sudden in the last 10 years it changes,' said Skelly. 'They're moving into areas where the physical environment is not like anything in their native range.' That implies that the cane toads have evolved more tolerance for the hotter climates they are now encountering. This is on top of the discovery last year that the toads at the forefront of the invasion had evolved longer legs than those in the interior of their range. The ability of animals to evolve so quickly needs to be factored into invasions, or the dangers of invasive species will likely be underestimated, argue Skelly and his colleagues Mark Urban, Ben Phillips and Richard Shine in an article in the March 28 issue of the Proceedings of the Royal Society-B.<ref>O'Hanlon, Larry (2007, April 2). "[http://news.discovery.com/animals/toxic-cane-toads-evolve-quickly.html Toxic Toads Evolving Quickly]." ''DiscoveryNews''.</ref>}}

====Human Evolution====

====Human microEvolution====

According to the assumptions of evolutionary theory, if evolution always went at the rate that we see today, there should be 160 times more differences between humans and apes. So rather than assume 'the present is the key to the past', scientists then decided that evolutionary rates today have accelerated for some reason. {{cquote|If humans had always evolved at this rate, the difference between modern humans and chimps should be 160 times greater than it really is. 'We realized we must be in a transient [phase], that evolution hasn't been going this fast for long in our species,' Harpending said. 'And so we wondered why.'<ref>Roach, John (2007, December 11). "[http://news.nationalgeographic.com/news/2007/12/071211-human-evolution.html Human Evolution Speeding Up]." ''National Geographic''.</ref>}} {{cquote|'I was raised with the belief that modern humans showed up 40,000 to 50,000 years ago and haven't changed,' explained Henry C. Harpending, an anthropologist at the University of Utah. 'The opposite seems to be true.'... If evolution had been proceeding steadily at the current rate since humans and chimps separated 6 million years ago there should be 160 times more differences than the researchers found. That indicates that human evolution had been slower in the distant past, Harpending explained.<ref>Schmid, Randolph E. (2007, December 10). "[http://www.washingtonpost.com/wp-dyn/content/article/2007/12/10/AR2007121001235.html?nav=rss_nation Researchers: Human Evolution Speeding Up]." ''The Washington Post''.</ref>}}

According to the assumptions of evolutionary theory, if evolution always went at the rate that we see today, there should be 160 times more differences between humans and apes. So rather than assume 'the present is the key to the past', scientists then decided that evolutionary rates today have accelerated for some reason. {{cquote|If humans had always evolved at this rate, the difference between modern humans and chimps should be 160 times greater than it really is. 'We realized we must be in a transient [phase], that evolution hasn't been going this fast for long in our species,' Harpending said. 'And so we wondered why.'<ref>Roach, John (2007, December 11). "[http://news.nationalgeographic.com/news/2007/12/071211-human-evolution.html Human Evolution Speeding Up]." ''National Geographic''.</ref>}} {{cquote|'I was raised with the belief that modern humans showed up 40,000 to 50,000 years ago and haven't changed,' explained Henry C. Harpending, an anthropologist at the University of Utah. 'The opposite seems to be true.'... If evolution had been proceeding steadily at the current rate since humans and chimps separated 6 million years ago there should be 160 times more differences than the researchers found. That indicates that human evolution had been slower in the distant past, Harpending explained.<ref>Schmid, Randolph E. (2007, December 10). "[http://www.washingtonpost.com/wp-dyn/content/article/2007/12/10/AR2007121001235.html?nav=rss_nation Researchers: Human Evolution Speeding Up]." ''The Washington Post''.</ref>}}

====Italian Wall Lizards====

====Italian Wall Lizards====

In 1971, scientists introduced 5 pairs of Italian Wall Lizards to a small island off the coast of Croatia. However, the Croatian War of Independence prevented the scientists from returning to the island for more than 30 years. When the war ended, tourism finally began again in 2004, allowing them to return. The researchers were unsure if the lizards would still be alive. Instead, they found the island swarming with lizards, which genetic testing showed to be descendants of their original 5. The new lizards had wiped out native lizard populations by evolving cecal valves, muscles between the large and small intestines, with which to digest native vegetation, an expanded gut structure, as well as a harder bite. {{cquote|Italian wall lizards introduced to a tiny island off the coast of Croatia are evolving in ways that would normally take millions of years to play out, new research shows. In just a few decades the 5-inch-long (13-centimeter-long) lizards have developed a completely new gut structure, larger heads, and a harder bite, researchers say... Such physical transformation in just 30 lizard generations takes evolution to a whole new level, Irschick said. It would be akin to humans evolving and growing a new appendix in several hundred years, he said. 'That's unparalleled. What's most important is how fast this is,' he said.<ref>Johnson, Kimberly (2008, April 21). "[http://news.nationalgeographic.com/news/2008/04/080421-lizard-evolution.html Lizards Rapidly Evolve After Introduction to Island]." ''National Geographic''.</ref>}}

In 1971, scientists introduced 5 pairs of Italian Wall Lizards to a small island off the coast of Croatia. However, the Croatian War of Independence prevented the scientists from returning to the island for more than 30 years. When the war ended, tourism finally began again in 2004, allowing them to return. The researchers were unsure if the lizards would still be alive. Instead, they found the island swarming with lizards, which genetic testing showed to be descendants of their original 5. The new lizards had wiped out native lizard populations by evolving cecal valves, muscles between the large and small intestines, with which to digest native vegetation, an expanded gut structure, as well as a harder bite. {{cquote|Italian wall lizards introduced to a tiny island off the coast of Croatia are evolving in ways that would normally take millions of years to play out, new research shows. In just a few decades the 5-inch-long (13-centimeter-long) lizards have developed a completely new gut structure, larger heads, and a harder bite, researchers say... Such physical transformation in just 30 lizard generations takes evolution to a whole new level, Irschick said. It would be akin to humans evolving and growing a new appendix in several hundred years, he said. 'That's unparalleled. What's most important is how fast this is,' he said.<ref>Johnson, Kimberly (2008, April 21). "[http://news.nationalgeographic.com/news/2008/04/080421-lizard-evolution.html Lizards Rapidly Evolve After Introduction to Island]." ''National Geographic''.</ref>}}