Wednesday, October 3, 2018

How Big Was MSNM V4047?

MSNM V4047:
MSNM V4047 is the largest specimen of any spinosauridae ever discovered, and it (was) the largest specimen of any carnivorous theropod as well. It was originally given to Spinosaurus in 2005, but in 2018 it was given to either Sigilmassasaurus or as a new species of spinosauridae. Whichever species this specimen belonged to, there's one question that I want solved: just how big was the ENTIRE animal? Only a maxilla (snout) out this animal exists. Originally, the entire head is said to have been 1.75 meters (6 feet) long (Sasso, 2005). Then in 2007-2016, the skull was given a length of 1.5-1.6 meters (5 feet) (Therrien and Henderson, 2007) (Hendrickx et al., 2016, "Size" Section). Many sizes were given for the total length of this specimen: 52-59 feet in 2005, then 49-50 feet in 2014, and now 51 feet in 2018. But after reading the scientific paper describing Oxalaia, and after reading more info. provided by other paleontologists, I began to think that MSNM V4047 was smaller than 50 feet.

This is a record of how many lengths have been given for this specimen: Dal Sasso in 2005 gave a length of 52-59 feet. Then in 2014, Ibrahim et al., (2014) gave a length of 49 feet. Paul Sereno gave a length of 50 feet. Now n 2018, the specimen was given a length of 51 feet. Other estimates given were: 46 feet by Gregory S. Paul in 2016, then 48-56 feet by Scott Hartman in 2913. However, he chose an absolute length of 51 feet. Gregory S. Paul said that the 2014 Spinosaurus reconstruction, using MSNM, was made incorrectly with specimens of other spinosauridae (Baryonyx and Suchomimus), and therefore he gave a smaller length. He did agree with the smaller legs though. In 2007, Therrien and Henderson gave a length of 41-47 feet. Lakin and Longrich (2018) used Therrien and Henderson's body lengths for MSNM V4047, but they gave an estimate of 39-49 feet based on a 1.75-meter skull. However, if I want to try and find THE most accurate size estimate for MSNM V4047, I think I'll have to do some math:

The Percentage Increase/Decrease Method:
1. Take new number and subtract it from original number.
2. Take that number and divide it by the original number and multiply by 100.
3. That number will by your percentage increase or decrease if it's negative.

Ex.: "Stan's" Femur is 130 and has a body length of 12.2 meters. "Wyrex" has a femur length of 132.7 cm.

132.7 - 130 = 2.7.
2.7 divided by (represented by "/") and multiplied by (represented by "*") equals 2.1.
(2.7/130*100 = 2.1)
2.1 is your percentage increase, or 2.1% increase.
12.2 m + 2.1% = 12.5 meters for "Wyrex."

Links:
Percentage Increase/Decrease Method Links:
"Percentage Change - Percentage Increase and Decrease." SkillsYouNeed:
https://www.skillsyouneed.com/num/percent-change.html
"Relative Increase." percentage.calculators.ro:
https://percentages.calculators.ro/15-percentage-increase-from-original-number-to-new-value.php

Size estimate: 12.5-18 meters. (Dal Sasso et al., 2005) (Therrien and Henderson, 2007) (Ibrahim et al., 2014) (Lakin and Longrich, 2018)(Henderson, 2018)

Rostrum Size: 101.0 cm. (My measurement from Dal Sasso et al., 2005, pg. 890 and 894) 
Premaxilla to Maxilla: 35 cm. (My Measurement in Dal Sasso et al., 2005) (My measurement in Hendrickx et al., 2016)
Maxilla to Antorbital Fossa: 66 cm (at best). (Measured on 4/26/20 in Dal Sasso et al., 2005, Figure 1, Drawing, 2nd One) (Measured in Ibrahim et al., 2020, Figure 129, "B")
Premaxilla up to 7th aveoli: 34 cm. (Measured on 4/26/20 in Dal Sasso et al., 2005, Figure 1, Drawing, 3rd one)

MSNM V4047 Rostrum (Dal Sasso et al., 2005, Figure 1). Scale bar is 20 cm:
Spinosaurus Specimen MNHM SAM 124:
Rostrum: 86 cm.
Maxilla to Antorbital Fossa: 46 cm.
Premaxilla to 7th aveoli: 21 cm.
Body: 11.7 meters. 


Rostrum:
101 - 86 = 15.
15/86*100 = 17.4% increase.
11.7 m + 17.4% = 45 feet (13.7 meters).

*Maxilla to Antorbital Fossa:
66 - 46 = 20.
20/46*100 = 43.5% increase.
11.7 m + 43.5% = 55 feet (16.8 meters).

*Update (3/14-16/21): Skull Reconstruction from Ibrahim et al., (2020)(a) Figure 129 (Scale bar is 40 cm):
Skull diagram (for reference) and reconstruction (Figure 129) (Scale bare is 40 cm):
Figure 129 Description:
Rostrum (Ibrahim et al., 2020(a), Figure 123) (Scale bar for A-D is 20 cm):
Rostrum Size: 99 cm (Measured on 3/15/21 in Ibrahim et a., 2020(a), Figure 123 A).
Premaxilla: 82 cm (at best) (Measured on 3/15/21 in Ibrahim et al., 2020(a), Figure 129 A).
Maxilla: 81 cm (at best) (Measured on 3/14/21 in Ibrahim et al., 2020(a), Figure 129 B).
Premaxilla to Maxilla: 30 cm (Measured on 3/15/21).
Dentary: 95 cm. (Figure 129, "B" [Below]) (Scaled up from new specimen).
Dentary Tooth Row: 68 cm (at best) (Measured on 3/20/21, Figure 129 B).

Suchomimus:
Maxilla: 59 cm.
Dentary: 67.7 cm.
Body: 10.0 meters.

Maxilla:
59 - 81 = 22.
22/59*100 = 37.3% increase.
10 m + 37.3% = 45 feet (13.7 meters).

Dentary:
95 - 67.7 = 27.3.
27.3/67.7*100 = 40.3% increase.
10 m + 40.3% = 46 feet (14.0 meters).

MSNM V4047's Total Length: 46 feet (14.0 meters).

MSNM V4047 is now considered to be Spinosaurus, according to Ibrahim et al., (2020) ("Taphonomy," "Spinosauridae").

Links:
Lakin and Longrich (2018) (Pg. 136 and 139):
2nd Copy: 
Arden et al., (2018):
Dal Sasso et al., (2005):
2nd Link: 
Hendrickx et al., (2016):
Therrien and Henderson. 2007: 
Ibrahim et al., (2014):
 ("Supplementary Materials"):
Posted by at