Featured Research

from universities, journals, and other organizations

Sex of early birds suggests dinosaur reproductive style: New way to identify gender of ancient avian species

Date:
January 22, 2013
Source:
Natural History Museum of Los Angeles County
Summary:
Paleontologists have discovered a way to determine the sex of a prehistoric bird species. Confuciusornis sanctus, a 125-million-year-old Mesozoic bird, had remarkable differences in plumage -- some had long, almost body length ornamental tail feathers, others had none -- features that have been interpreted as the earliest example of avian courtship. However, the idea that male Confuciusornis birds had ornamental plumage, and females did not, has not been proven until now.

Reconstruction of Confuciusornis sanctus.
Credit: Stephanie Abramowicz, NHM Dinosaur Institute

In a paper published in Nature Communications on January 22, 2013, a team of paleontologists including Dr. Luis Chiappe, Director of the Natural History Museum of Los Angeles County's (NHM) Dinosaur Institute, has discovered a way to determine the sex of a prehistoric bird species.

Related Articles


Confuciusornis sanctus, a 125-million-year-old Mesozoic bird, had remarkable differences in plumage -- some had long, almost body length ornamental tail feathers, others had none -- features that have been interpreted as the earliest example of avian courtship. However, the idea that male Confuciusornis birds had ornamental plumage, and females did not, has not been proven until now. Chiappe and the team studied hundreds of Confuciusornis fossils unearthed from rocks deposited at the bottom of ancient lakes in what is today northeastern China and found undisputed evidence of the gender difference: medullary bone.

Chiappe conducted the study with Anusuya Chinsamy of the Department of Biological Sciences, University of Cape Town, South Africa; Jesús Marugán-Lobón of Madrid's Universidad Autonóma, Cantoblanco; Gao Chunling and Zhang Fengjiao of the Dalian Natural History Museum in China.

"Our discovery provides the first case of sex identification in an ancient bird, an animal closely related to dinosaurs, such as the famous Velociraptor," said Chiappe. "When people visit dinosaur exhibits, they often want to know if the skeletons are male or female. We have nicknames like Thomas and Sue, but of all the thousands of skeletons of dinosaurs or early birds found around the world, only the sex of a few has been determined."

According to Chinsamy, the bone histologist on the team, "Just like modern hens, female Confuciusornis birds that lived 125 million years ago deposited this special bone inside their long bones, and then used it to make the calcium-rich eggshells." Finding such tissue -- present during a short period of time in reproductively active females -- in a specimen that lacked long feathers proved that those birds without ornamental plumage are females.

"This now permits us to assess gender differences in growth and development of this Mesozoic bird," she said.

But while this discovery offers evidence that both early and modern female avian species were essentially using the same physiological strategy to reproduce, it also spotlights an important difference in when they sexually matured.

"In human terms, knowing the sex of these specimens sheds light on when these early birds begin puberty," said Chiappe, "Now we know that early birds began reproducing way before they were full grown, a pattern that contrasts with what we know of living birds, which typically begin reproducing after they reach full body size." In that way, ancient birds produced offspring like dinosaurs, which also began to reproduce before they were fully grown.

The specimens, housed at the Dalian Natural History Museum in northeastern China, had been excavated from rocks formed at the bottom of ancient lakes in a forested environment surrounded by volcanoes. Ancient catastrophes, presumably related to volcanic eruptions, killed large numbers of birds and other animals, whose bodies were buried deep in the lake mud that helped minimize decay and preserving the organs, skeletons, and plumage. "This discovery is part of the big picture of understanding the early evolution of birds,'' Chiappe said, "and how living birds became what they are."


Story Source:

The above story is based on materials provided by Natural History Museum of Los Angeles County. Note: Materials may be edited for content and length.


Journal Reference:

  1. Anusuya Chinsamy, Luis M. Chiappe, Jesús Marugán-Lobón, Gao Chunling, Zhang Fengjiao. Gender identification of the Mesozoic bird Confuciusornis sanctus. Nature Communications, 2013; 4: 1381 DOI: 10.1038/ncomms2377

Cite This Page:

Natural History Museum of Los Angeles County. "Sex of early birds suggests dinosaur reproductive style: New way to identify gender of ancient avian species." ScienceDaily. ScienceDaily, 22 January 2013. <www.sciencedaily.com/releases/2013/01/130122111654.htm>.
Natural History Museum of Los Angeles County. (2013, January 22). Sex of early birds suggests dinosaur reproductive style: New way to identify gender of ancient avian species. ScienceDaily. Retrieved February 1, 2015 from www.sciencedaily.com/releases/2013/01/130122111654.htm
Natural History Museum of Los Angeles County. "Sex of early birds suggests dinosaur reproductive style: New way to identify gender of ancient avian species." ScienceDaily. www.sciencedaily.com/releases/2013/01/130122111654.htm (accessed February 1, 2015).

Share This


More From ScienceDaily



More Fossils & Ruins News

Sunday, February 1, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Discovery Of 'Dragon' Dinosaur In China Could Explain Myths

Discovery Of 'Dragon' Dinosaur In China Could Explain Myths

Newsy (Jan. 30, 2015) — A long-necked dinosaur from the Jurassic Period was discovered in China. Researchers think it could answer mythology questions. Video provided by Newsy
Powered by NewsLook.com
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

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