My Prehistoric Saga: November 2018

Updated on 9/12/19:
FMNH PR 2081/BHI 2033 ("Sue"):

FMNH PR 2081, or "Sue," previously known as BHI 2033, is stated as being the largest specimen of T-Rex to have ever been discovered. However, over the years her size has gone up and down. When she was discovered, she was stated as being 41 feet (12.5 meters) "plus or minus a foot" (Larson, 1994). Then in 2000-2008, her skeleton was put on display and was given a length of 42 feet (12.8 meters) (Field Museum, 2008). Then later on, she was given 40.5 feet (12.35/12.4 meters). In 2011, she was given 40 feet (12.29/12.3 meters) (Hutchinson, 2011). This size estimate has been used everywhere and is still used today. Then in 2014, she was given 41 feet again (12.5 meters) (Ibrahim et al., 2014). In 2007, she was given 11.7/12.0-12.0 meters (Therrien and Henderson, 2007). This was based on her 1.39-meter skull. Then in 2017 and 2018, she's back to being 42 feet (12.8/13.0 meters).

My question is just how big is she really? Well, let's 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

Larson (1994), Brochu (2003), Erickson et al., (2004), Brusatte et al., (2010), Brusatte and Carr (2016), and Gignac and Erickson (2017) gave "Sue" a length of 12.5-12.8 meters. However, Brochu (2003) got "Sue's" length from Larson (1994). In order to extrapolate a size for "Sue" myself, I measured her right femur in Brochu (2003) (pg. 112).

"Sue's" Right Femur (Brochu, 2003, pg. 112, "A," Posterior View). (Scale bar is 30 cm):

(Measurements taken on 9/4-8/19):
Straight Side: 137.0 cm. (Surprisingly, the 137-cm length was stated in "A Tyrannosaurus Rex Named Sue," 2001)
Short side with femoral head: 135 cm.
Total Length (From femoral head to tip of longest side): 143 cm (at best). (Measured on 9/8/19)

Now, let's see how large "Sue" is:

Ex.: CM 9380 and "Samson/Z-Rex":
Femurs: 136 cm.
Bodies: 12.9 meters.

The 137-cm femur length:
137 - 136 = 1.
1/136*100 = 0.7% increase.
12.9 m + 0.7% = 13.0 meters for "Sue."

Total femur length:
136 - 143 = 7.
7/136*100 = 5.2% increase.
12.9 m + 5.2% = 45 feet (13.6 meters) for "Sue."

Note: Here's how I was able to obtain CM 9380's and "Samson's" sizes:
1. "Stan":
Femur: 130 cm. (BHI)

MOR 555's Measurements (Farlow et al., 1995):
Femur: 128 cm.
Body: 11.96 or 12.0 meters. (Farlow et al., 1995) (Natural Museums Scotland)

128 - 130 = 2.
2/128*100 = 1.6% increase.
12.0 m + 1.6% = 12.2 meters for "Stan."

Note: MOR 555's femur is actually 130 cm, so it's 12.2 meters as well.

2. "Wyrex":
Femur: 132.7 cm. (Bell et al., 2017, Supplementary Materials)

BHI 3033 ("Stan"):
Femur: 130.0 cm.
Length: 40 feet (12.2 meters).

132.7 - 130 = 2.7.
2.7/130*100 = 2.1% increase.
12.2 m + 2.1% = 12.5 meters for "Wyrex."

3. "Hank":
Femur: 133.4 cm (52.5 inches).
Humerus: 35.6 cm.

"Wyrex":
Femur: 132.7 cm.
Body: 12.5 meters.

133.4 - 132.7 = 0.7.
0.7/132.7*100 = 0.5% increase.
12.5 m + 0.5% = 12.6 meters.

4. CM 9380 and "Samson":
CM 9380's Femur: 136 cm. (Measured in Weishampel et al., 2004, pg. 126, Cranial View) (Taken 8/3/19)

"Hank":
Femur: 133.4 cm.
Body: 12.6 meters.

136 - 133.4 = 2.6.
2.6/133.4*100 = 2% increase.
12.6 m + 2% = 42 feet (12.9 meters) for CM 9380.

"Samson's" Original Femur Length: 1.36 meters. (Glut, 2002; stated on the Theropod Database website)

Glut (2002) from the Theropod Database: