Apatosaurus ajax

 

Apatosaurus ajax (Marsh, 1877) 
Dinosauria 
Sauropoda 
Diplodocoidea 
Diplodocidae 
Apatosaurinae 

Kimmeridgian to Tithonian (Late Jurassic) 
Morrison Formation 
Colorado, New Mexico, Oklahoma, Utah, Wyoming; United States 

Length: 21 - 30+ m? 

With some specimens significantly larger than most apatosaurines (e.g. OMNH 1670), Apatosaurus ajax was likely one of the largest animals to have ever walked the Earth. 

Monday, April 19th, 2021 

Apatosaurus louisae

 

Apatosaurus louisae (Holland, 1916) 

Dinosauria 

Sauropoda 

Diplodocoidea 

Diplodocidae 

Apatosaurinae 

Kimmeridgian - Tithonian (Late Jurassic) 

Morrison Formation 

Colorado, New Mexico, Oklahoma, Utah, Wyoming; United States 

Length: 21 - 23 m 

It has been hypothesized that Apatosaurus louisae used their long thick necks in intraspecific combat, similarly to modern day giraffes or elephant seals (Source: http://www.miketaylor.org.uk/dino/pubs/svpca2015/abstract.html#gsc.tab=0). 

Monday, April 5th, 2021