4.1.1 Background
 
 

Lystrosaurus - A Therapsid (mammal-like reptile) that was present in very large numbers (running into the millions) in Gondwana during the Triassic period. (Gondwana was the supercontinent consisting of the landmasses of South America, Africa, Antarctica, Australia and India that split and drifted apart during the periods following the Triassic.) It is a member of a group of therapsids called Dicynodonts, characterized by their horny beaks and only two teeth - the canines, which grew quite large and appeared like tusks. They lived in sizable herds beside water sources (rivers and lakes), and were herbivorous. Probably the major component of their diet consisted of plants called horsetails, which grew more than a meter tall. Lystrosaurus are particularly interesting because they were among the few Dicynodonts to appear in the fossil record after the great extinction event at the end of the Permian period, which wiped out 95 percent of all life on earth. In fact, the Lystrosaurs were present with the first dinosaurs. There were at least two species of Lystrosaur: a very large one with a flat-fronted face that grew to the size of a big Brahman bull, and a smaller one with a more rounded snout. They were sprawling animals, chunky and lumbering and probably incapable of any great burst of speed. They would not have been scaly or furry, but would have had tough leathery skins. Lystrosaurus are creatures that inhabited the ancient Karoo area of South Africa.

Pronunciation guide: Lystrosaurus (Liss- tro- SAW- russ) Dicynodont (Dy-SY-no-dont) Gondwana (Gone-DWA-na) Triassic (Try-ASS-ik) Permian (PUR-mee-un). [15]

The Permian started around about (approximately and all that) 286 million years ago and ended with the start of the Triassic about 248 million years ago. Your first dinosaurs therefore pitched up about the middle of the Triassic (220 million years ago or so).

The Materialise software was applied extensively during the conversion process. This was a very interesting case study. What made it so interesting was that the fossil’s skull was and is still encapsulated in rock. The big advantage is that the rock can now be electronically removed to display the fossil, with the aid of CAT and 3D computer image processing. The cost and time saving are astronomically. Imagine an archeologist spending months to grind the rock away, compared to this new process that will take less than a week. This fossil was scanned at two hospitals, Hydromed and Krugersdorp Private Hospitals. Different apparatus was used hoping to get better results from the more recent spiral CAT scanners.
 
 
 
 

4.1.2 Conclusion
 
 

Referring to the following data sheet, the fossil’s skull can be retrieved from the rock in about 14 hours and costs about R2400 excluding CAT scanning. 3D renderings can be supplied at this stage. 3D data is also available, virtual reality programs can be used to realistically visualize the fossil. Another estimated R2000 and two days will allow one to produce a 3D physical prototype. Compare this with the conventional method, taking several weeks to extract the fossil from the rock. There may not be a great cost saving at this stage. With this method, one can very quickly determine what is inside the rock. Several weeks may be spent extracting the fossil from the rock and the fossil may not be of great value or importance. It will therefore streamline the process. Making use of this technology will enable the anthropologist to be effective and efficient.

4.1.2.1 Images
 
 
 

Figure 4.1.2 .1 The Lystrosaurus.	Figure 4.1.2 .2 The Lystrosaurus encapsulated in rock.
Figure 4.1.2 .3 2D CAT scanned slice Nr. 138	Figure 4.1.2 .4 3D rendering of the top twenty slices
Figure 4.1.2 .5 3D rendering of the skull	Figure 4.1.2 .6 3D rendering of the skull

 

4.1.3 Lystrosaurus Data Sheet:

 

	Description	Options (Default)	Data K’dorp	Data Hydromed
1	CT Image Names		fos.xxx	4s4I
2	Patient/Project Name		fos.pat	4s4i.pat
3	Number of First Input Image		27/01	68
4	Number of Last Input Image		157/99	133
5	Number of First Output Image		000	000
6	CT or MRI	CT, MRI	CT	CT
7	Horizontal Nr. Of Image Pixels	0 to 65535 (265,512,1024)	512	512
8	Vertical Nr. Of Image Pixels	0 to 65535 (265,512,1024)	512	512
9	Number of Images per File	(1)	1	1
10	File Swap Format (0,3)	0,3	CCELSC	CCGEADVA
11	Pixel Type	B,UB,S,US,L,UL,F	-	-
12	Header Size	*see formula below	-	-
13	Inter Image Header Size	0	-	-
14	Add Value	0 to 4095	-	-
15	Scale Value	0 to 4095	-	-
16	Table Position	(mm)	0	0
17	Distance Between Slices	(mm)	1	1
18	Slice thickness	(mm)	1	1
19	Pixel Size SQ.	F.O.R./Nr. Hor. Pixels (mm)	0.47	0.43
20	Gantry Tilt Angle	Degrees	0	0
21	Field of Reconstruction/View	(mm)	240	220
22	Number of Images		130	65
23	File Size of CAT Image	Kb	270-280	270-280
24	File Size of Converted Image	Kb	135	135
25	.3dd file size	Mb	1.4 (X.srf)	1.4 (X.srf)
26	.STL file size	Mb	not grown	Not grown
27	RP Method	(SLA,FDM,OTHER)	-	-
28	.IGS file size	Mb	-	-
29	RP Slice file size	Mb	-	-
30	RP Download File size	Mb	-	-
31	Grow Time	Hour	-	-
32	Tip size	(T12, T25)	-	-
33	Slice Thickness	(0.01", 0.014")	-	-
34	Finishing Time	Hour	-	-
35	Processing Time	Hour	5	10
36	Data Retrieval Time	Hour	4	4
37	Total Cost	Rand		=14*150+300 =2400