Pachycephalosaurus Timeline

 
 
Pachycephalosaurus   >   Timeline

   



Pachycephalosaurus Timeline

Time
 
Event
 
Approximately
220 million years ago
 
First dinosaurs evolve during the Triassic period.
 
Approximately
76 million years ago
 
First Pachycephalosaurus appears during the Cretaceous period.
 
Approximately
65 million years ago
 
Cretaceous-Tertiary extinction event: All non-avian dinosaurs (including Pachycephalosaurus) go extinct.

The K/T Extinction Event may have been caused by an asteroid impact:
K/T Extinction Event may have been caused by an asteroid impact

 
1850s
 
Unknown fossil hunter finds Pachycephalosaurus in the Lance Formation in Southeastern Montana. The earliest name used to refer to the animal is "Tylosteus".

Map of Hell Creek and Lance Formations:
Map of Hell Creek and Lance Formations

 
1872
 
Joseph Leidy identifies the fossil as belonging to the armor of a reptile or an armadillo-like animal (more than a century later it turned out to be a bone from the knobs on Pachycephalosaurus's skull).

Joseph Leidy:
Joseph Leidy

 
1931
 
What is today known as Pachycephalosaurus wyomingensis is named by Charles W. Gilmore as Troodon wyomingensis.

Charles W. Gilmore:
Charles W. Gilmore

 
1945
 
Barnum Brown and Erich Maren Schlaikjer, using newer and more complete specimens, establish the Genus Pachycephalosaurus. They identify two species: Pachycephalosaurus reinheimeri and Pachycephalosaurus grangeri (although neither are generally recognized as distinct species today).

Barnum Brown:
Barnum Brown


 
1985
 
Donald Baird successfully campaigns to get the officially recognized name for the Genus to be "Pachycephalosaurus", even though the normal rules of zoological nomenclature would dictate "Tylosteus", since this was the first name used. As a result of this the only species generally recognized today is Pachycephalosaurus wyomingensis.

Pachycephalosaurus wyomingensis
at the Academy of Natural Sciences, in Philadelphia, Pennsylvania:
Pachycephalosaurus wyomingensis

 







Linking to This Page

We do hope that you find this site useful. We welcome people linking to this website or citing us.

The URL of this web page, is:


If you want to link to this web page from your own web site, you can use the following HTML code:





 
      Pachycephalosaurus Information:

   Books

   Classification

   Facts

   Name

   Pictures

   Size

   Timeline

   Toys



Links:

Dinosaur Coloring

Dinosaur Hangman

Dinosaur Jokes

Dinosaur Museums

Dinosaurs News

Dinosaurs Parks

Dinosaur Types

Science Downloads

Science eBooks



Educational Products

Education Downloads

School eBooks

Science eBooks

Science Project Downloads



More Types of Dinosaurs

Ankylosaurus

Ceratosaurus

Kentrosaurus

Protoceratops

Spinosaurus

Styracosaurus

Tyrannosaurus rex
 
 
 
 
 

 
 
Copyright © 2008-2024, Answers 2000 Limited

Disclosure: Our company's websites' content (including this website's content) includes advertisements for our own company's websites, products, and services, and for other organization's websites, products, and services. In the case of links to other organization's websites, our company may receive a payment, (1) if you purchase products or services, or (2) if you sign-up for third party offers, after following links from this website. Unless specifically otherwise stated, information about other organization's products and services, is based on information provided by that organization, the product/service vendor, and/or publicly available information - and should not be taken to mean that we have used the product/service in question. Additionally, our company's websites contain some adverts which we are paid to display, but whose content is not selected by us, such as Google AdSense ads. For more detailed information, please see Advertising/Endorsements Disclosures

Our sites use cookies, some of which may already be set on your computer. Use of our site constitutes consent for this. For details, please see Privacy.

Click privacy for information about our company's privacy, data collection and data retention policies, and your rights.

Contact Us   Privacy   Terms of Use   Advertising/Endorsements Disclosures
CERTAIN CONTENT THAT APPEARS ON THIS SITE COMES FROM AMAZON SERVICES LLC. THIS CONTENT IS PROVIDED 'AS IS' AND IS SUBJECT TO CHANGE OR REMOVAL AT ANY TIME.
CERTAIN CONTENT THAT APPEARS ON THIS SITE,COMES FROM AMAZON EU S.à r.l. THIS CONTENT IS PROVIDED 'AS IS' AND IS SUBJECT TO CHANGE OR REMOVAL AT ANY TIME.


In Association With Amazon.com
Answers 2000 Limited is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.
In Association With Amazon.co.uk
Answers 2000 Limited is a participant in the Amazon EU Associates Programme, an affiliate advertising programme designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.co.uk.
As an Amazon Associate, our company earns from qualifying purchases. Amazon, the Amazon logo, Endless, and the Endless logo are trademarks of Amazon.com, Inc. or its affiliates.


All trademarks are property of their respective owners.
All third party content and adverts are copyright of their respective owners.

Some graphics on our web sites are Copyright (C) 1997-2000 Hemera Technologies Inc., and used under license. All such pictures are provided for viewing purposes only and are not to be saved or downloaded. All such pictures of recognizable individuals are models and used for illustrative purposes only, and not meant to imply any association or endorsement of said individual with any product or service.