Dreadnoughtus

Dreadnoughtus meaning "fearing nothing" and a type of warship is a genus of giant titanosaurian dinosaur. Its fossilised skeleton was found in the Upper Cretaceous of Santa Cruz province, Argentina. These rocks date from 84–66 million years ago (mya).

This is one of the largest of all known terrestrial vertebrates. It has the greatest mass (weight) of any land animal that has been calculated. They used using limb bone measurements for the calculation.

Dreadnoughtus schrani is the most complete skeleton of a large titanosaurian sauropod dinosaur. Types of bones is the most important statistic. The completeness statistics for Dreadnoughtus schrani are as follows:
116 bones out of ~256 in the entire skeleton (including the skull) = 45.3% complete
115 bones out of ~196 in the skeleton (excluding the skull) = 58.7% complete
100 types of bones out of ~142 types in the skeleton (excluding the skull) = 70.4% complete

The specimen was probably not fully grown at the time of its death. The histology of its humerus, shows a lack of an outer layer of bone found only in fully-grown vertebrates. There is a lot of fast-deposited or still-growing bone tissue. Therefore, the specimen was still growing at the time of its death. It is unknown how large this individual would have grown if it had lived a full life.

 Estimates 
As a matter of basic science, the estimates of dimensions such as the mass (weight) of extinct animals are very rough figures. To avoid the pretence of spurious accuracy. we only give rounded figures here. Moreover. all the skeletons are incomplete, which means that even length (the easiest dimension to estimate) cannot be given exactly. Published estimates by scientists are just that: estimates. Estimation is an approximation given when information is not clear or is incomplete. It is like making an educated guess.

It is usual for estimates of mass (weight) to vary between experts. Using the same basic data, the weight of Dreadnoughtus has been estimated as:

About 59.3 metric tons (65.4 short tons), or 59,291 kilograms. 
Between 35 and 40 metric tons (39 to 44 short tons), 
About 30 metric tons (33 short tons), based on a 20% shorter torso.

There is a ~x2 difference between the heaviest and lightest estimates, and that is not at all unusual for this type of calculation.

 Size 
+ Dreadnoughtus dimensions  Dimension metric imperial Mass     Total length  26 m  85 ft Head and neck length  12.2 m  40 ft Neck-only length  11.3 m  37 ft Torso and hip length  5.1 m  17 ft Tail length  8.7 m  29 ft Shoulder height  ~ 2 stories (6 m)  ~ 2 stories (20 ft)

 Comparisons 

 Sauropod  Group  metric tons  short tons Dreadnoughtus schrani  Titanosauria  59.3   65.4 Brachiosaurus altithorax  Brachiosauridae  56.3   62.1 Turiasaurus riodevensis  Turiasauria  50.9   56.1 Elaltitan lilloi  Titanosauria  42.8   47.2 Futalognkosaurus dukei  Titanosauria  38.1   42 Giraffatitan brancai  Brachiosauridae  34   37.5 Diplodocus longus  Diplodocidae  14.8   16.3

 References 

Category:Titanosaurs