Featured Research

from universities, journals, and other organizations

Dinosaur Fossils Reveal Evolution's Big Picture, Says Paleontologist

Date:
June 25, 1999
Source:
American Association For The Advancement Of Science
Summary:
Dinosaur fossils are providing the answers to some of scientists' biggest questions about evolution, according to paleontologist Paul Sereno, who has assembled the most up-to-date picture yet of dinosaur evolution in the 25 June 1999 issue of Science.

Washington, DC - Dinosaur fossils are providing the answers to some of scientists' biggest questions about evolution, according to paleontologist Paul Sereno, who has assembled the most up-to-date picture yet of dinosaur evolution in the 25 June 1999 issue of Science.

Related Articles


In his article, which is part of Science's special issue about evolution, Sereno shows how dinosaur fossils hold the clues to questions such as: How does an upstart group of species beat out the dominant group? How do organisms develop nifty new tricks like flying? And how does the breakup of a supercontinent affect the course of evolution?

These major events in the history of life, involving global patterns and trends that occur over millions of years, are crucial aspects of evolution not accessible from the anatomy and genes of living animals. "Certain questions about evolution can only be investigated at the grandest scales using the fossil record," said Sereno, who is from the University of Chicago.

The radiation of new dinosaur species was a spectacular and long-lasting success. In fact, during the Mesozoic era (248 to 65 million years ago), all the land animals more than one meter long were dinosaurs. The only other group of animals to dominate their ecosystem so thoroughly were the mammals of the following era, the Cenozoic (65 million years ago to the present).

Paleontologists have argued about the secret of the dinosaurs' success for years. Does one group of animals make it to the top by gradually pushing other, less well-adapted animals out of the picture? Or does the group take a more opportunistic approach, moving in after a mass extinction event has wiped out its competition? Recent dinosaur fossil finds suggest the latter, Sereno and other scientists conclude. For example, the dinosaurs' heyday didn't begin until at least 15 million years after the first dinosaurs appeared on Earth, but it did coincide with a mass extinction that killed off many other reptiles. It now looks like both the dinosaurs and the large mammals that followed the dinosaurs' extinction came to dominate their world essentially by accident-not as the inevitable outcome of natural selection.

Of course, dinosaurs didn't disappear completely. Some evolved into birds, and the stages of this transformation are recorded in the fossil record. According to Sereno, recent discoveries have been particularly useful in shedding light on how animal groups develop major new abilities such as flying. Several spectacular finds in recent years have shown scientists just how effectively dinosaurs recycled many of their features that had been originally designed for other purposes. Once the "avian dinosaurs" were launched, they quickly evolved in ways that helped them fly even better, shrinking several times in body size, for example.

A third big question about evolution concerns the role that major changes in geography, caused by the shifting of the Earth's tectonic plates, play in the evolution of new species. The dinosaurs are a prime subject for studying this problem, because they reached the height of their diversity during the breakup of the supercontinent Pangaea in the early Cretaceous period (about 150 to 100 million years ago). It is now becoming clear that this diversity arose as a patchwork of regional extinctions of certain species and replacements by others, not by the creation of new lineages, which has been considered as an alternative possibility.

Eventually, the dinosaurs met their demise at the end of the Cretaceous. But Sereno isn't letting the mystery of these animals' disappearance overshadow the wealth of information they left behind during their reign. "The Mesozoic world and the dinosaurs offer a look into one of the grandest experiments in the history of life," Sereno said.

Science's special issue on evolution also contains five other articles, an editorial, and a special news package. One article looks at recent genetic evidence that has shaken scientists' confidence in the traditional classification system used to assemble the universal "tree of life." Another discusses recent progress in understanding the influences that shaped the early unfolding of animal diversity during an event known as the Cambrian explosion. A third provides insight into why nature chose RNA as the fundamental molecule for life. Two other articles discuss the evolution of species interactions and how paleontology is becoming an increasingly interdisciplinary endeavor. The special section also includes an editorial by Stephen Jay Gould about evolution and creationism, and a special package of three news articles.


Story Source:

The above story is based on materials provided by American Association For The Advancement Of Science. Note: Materials may be edited for content and length.


Cite This Page:

American Association For The Advancement Of Science. "Dinosaur Fossils Reveal Evolution's Big Picture, Says Paleontologist." ScienceDaily. ScienceDaily, 25 June 1999. <www.sciencedaily.com/releases/1999/06/990625074549.htm>.
American Association For The Advancement Of Science. (1999, June 25). Dinosaur Fossils Reveal Evolution's Big Picture, Says Paleontologist. ScienceDaily. Retrieved January 30, 2015 from www.sciencedaily.com/releases/1999/06/990625074549.htm
American Association For The Advancement Of Science. "Dinosaur Fossils Reveal Evolution's Big Picture, Says Paleontologist." ScienceDaily. www.sciencedaily.com/releases/1999/06/990625074549.htm (accessed January 30, 2015).

Share This


More From ScienceDaily



More Fossils & Ruins News

Friday, January 30, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Battle of Waterloo Artefacts Go on Display at Windsor Castle

Battle of Waterloo Artefacts Go on Display at Windsor Castle

AFP (Jan. 29, 2015) Artefacts from the Battle of Waterloo go on display at Windsor Castle to mark the 200th anniversary of the momentous battle. The exhibition includes contemporary prints, drawings and personal belongings of French Emperor Napoleon. Duration: 00:31 Video provided by AFP
Powered by NewsLook.com
Mideast Skull Find Sheds Light on Human Ancestors' Trek

Mideast Skull Find Sheds Light on Human Ancestors' Trek

AFP (Jan. 29, 2015) A 55,000-year-old partial skull found in the Middle East gives clues to when our ancestors left their African homeland, and strengthens theories that they co-habited with Neanderthals. Duration: 00:54 Video provided by AFP
Powered by NewsLook.com
Scientists Say Earliest Snakes Lived Alongside The Dinosaurs

Scientists Say Earliest Snakes Lived Alongside The Dinosaurs

Newsy (Jan. 28, 2015) Wrongly categorized as lizard fossils, snake fossils now show the reptile could have developed earlier than we thought — 70 million years earlier. Video provided by Newsy
Powered by NewsLook.com
Ancient Skull May Mark Where Humans First Met Neanderthals

Ancient Skull May Mark Where Humans First Met Neanderthals

Newsy (Jan. 28, 2015) A 55,000-year-old skull fragment found in an Israeli cave might mark one of the first areas where modern humans and Neanderthals met. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins