Did Ratha really exist?

Many readers have asked me what prehistoric species Ratha is based on. Originally, I chose Nimravus, a leopard-like creature from the early Miocene. I was inspired the Charles R. Knight painting of Nimravus fighting with another early sabertoothed nimravid, Eusmilus. 

 Nimravus gave its name to its family, which is called Nimravidae. Individual species are nimravids, such as the one shown at right.

Many years later, I learned about a new fossil creature called Dinaelurus. There was speculation that this animal might have been a cheetah-like "cursorial predator". 

 ( "Cursorial" means an animal that courses or runs down its prey.) 

At that time, no-one had drawn a reconstruction of Dinaelurus similar to the one of Nimravus above.               decided to try, but it was hard to find a drawing or                or photo of the skull.  I finally ended up enlarging a very tiny drawing in an evolutionary tree illustrating  the             development of the nimravids.                                             Image from John Day Formation website

 

 It worked well enough for me to start the clay sculpture shown below on the left. I intended to use the model as a reference for sketches.  I was amazed at how real it looked in the photograph even though the model is scaled down by roughly one-third. 

 

Photo and model by Clare Bell, 2006                                                                    Image from the paper by Eaton

  

To  the left is the skull of Dinaelurus   crassus, from  the John Day formation in Oregon. This drawing was part of the original scientific paper by Eaton describing the fossil, and is one of three illustrating front, top and side views . It was sent to me by Spanish artist Maricio Anton, who did the beautiful illustrations for The Big Cats and Their Fossil Relatives, by Alan Turner. I had emailed him a query about Dinaelurus and he very kindly emailed me the images.

I used them to correct and complete the model above, although I retained the skull flange shown in the original reference. I think the fossil in the drawing had the back of the flange broken off.  Or maybe I need to re-do the sculpture. The model is slightly rotated in the photo.

Here's my sculpture of Dinaelurus crassus, built on the above clay skull.  I built up the form anatomically, adding muscles and other bits.

 

 

 

So far, researchers have only found the fossil skull of Dinaelurus crassus.  They have extrapolated certain features, such as a shortened face (as compared to its cousin, Nimravus) and enlarged nasal passages (cheetahs have those in order to get enough air into their lungs while chasing prey at more than 70 mph), to guess that this animal was a cheetah-like cursorial predator.

 

 

                                                        

                                                                                    Photo and model by Clare Bell 2007

 

To envision Ratha's body structure, I looked at illustrations of cheetah and puma skeletons in Turner and Anton's book.  I blended the two, giving her essentially the back legs of a cheetah, (made more robust)  for speed and power. She also has a long cheetah-like tail for balance in jumps and turns. Her front legs and shoulders are like those of a "stretched" puma, for power in pulling down and wrestling prey. 

As you can see in the annotated sketch below, I drew the bones first, then outlined the body based on musculature. As described in the book, she is a solid fawn rather than spotted, but I gave her the cheetah "tear-line" facial markings since I was inspired by the cover of the original Ratha's Challenge.

 

 

 

Like a puma, Ratha has a slightly raised rump, and she has similar jumping abilities. She also climbs trees like a puma.  Her top speed in a sprint is less than a cheetah, but greater than a puma.  She probably has greater endurance than a cheetah.

 

This sketch was a good first step, but I wasn't completely satisfied with it.

The hindquarters looked too large as compared to the forequarters, and the head looked too small. To get a brain-to-body ratio closer to that of a human, I had to enlarge the head without distorting it.  

I wasted many pieces of paper trying.  It wasn't until I did the sculpture shown above that I got close to what I wanted.

 

Why base Ratha on a cheetah-like animal?

Originally I thought of the Named as  puma-like, and described them based on that image, although I did add in a little lion-pride behavior, such as the cub nursery.  When CBS Storybreak did an animated adaptation of Ratha's Creature in the mid 1980's, the Named were portrayed as "a civilization of mountain lions" on another world.

As I developed the characters, especially the herding teacher, Thakur, they took on more cheetah-like characteristics. Thakur's speed and his enjoyment of running, is described in Clan Ground. The Named herders also have to make fast dashes to cut off straying or unruly herd-beasts. These runs would be similar to cheetahs sprinting after their prey.

There was also an interesting graphic development that pushed me toward the cheetah-like concept.

Covers for the later Ratha books showed a very cheetah-like animal, since the illustrator had also done a cover for Tomorrow's Sphinx, which is about cheetahs in past and future Egypt. Internet fans of the series began to think of the Named as very cheetah-like, and I agreed, since I liked the image.

Here's the cover of the original Sphinx hardback edition. The same artist did the Ratha's Challenge cover

 

Both photos by Clare Bell 2006. On the right, a very lovely blend of puma and cheetah .

 

Scientists had also discovered that the puma and cheetah appeared to be closely related.  The North American cheetah-like cat Miracynonyx is also thought to be ancestral to today's mountain lions. 

So it wasn't that large a step from a puma-like animal to a cheetah-like animal.  However, I did not change the earlier books when they were reprinted. People liked them as they were, and everyone forms their own vision of the Named anyway.

But I still had an annoying little inconsistency.  The jacket flap copy for Ratha's Creature, the first in the series, said that the story was set 20-25 million years ago in the early Miocene. Cheetahs and cheetah-like ancestors such as Miracynonyx didn't exist at that time.  They appeared much later, in the Pliocene. Acinonyx jubatus, the present-day cheetah, appeared in the Pleistocene era, no more than 5 million years ago.