Are Tigers 'Brainier' Than Lions?

[peter]

(01-23-2017, 08:45 AM)johnny rex Wrote:

(10-14-2015, 12:00 AM)GrizzlyClaws Wrote: He claims these two skulls, Amur and Bengal respectively, measure about 40 cm.

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So @peter have you already measured these skulls yourself? Are the measurements on both of these skulls confirmed to be 16 inches?

No to both questions.

The longest Amur tiger skull measured by V. Mazak was 383 mm., whereas the longest skull from India was 378 mm. The longest lion skull he measured was 402 mm. in greatest total length. This is the skull in the collection of the Zoological Museum of Amsterdam mentioned in other posts. I measured the skull in 2004 and got to 408 mm. Same for the conservator and a biologist who happened to be there. Anyway.

The tables V. Mazak published are often used. The reason is he was one of the few interested in skulls. In the third edition of his great book 'Der Tiger' (German edition, 1983, pp. 196), Mazak wrote he had measured 280 skulls. A pity that his example hasn't been followed.

The question regarding tiger skulls is if they can reach 15,5 or 16 inches. Baikov (1925) said yes and he wasn't the only one. Same for Indian tigers. The JBNHS published different letters of hunters who had shot very large tigers. Two of these had a skull of 16 inches in greatest total length. Based on the details they provided, they could have been right.  

I'm not too sure about taxidermists. The skull of a 10.2 (measured 'over curves') tiger shot by the daughter of Sir John Hewett, according to the taxidermist that measured the skull, allegedly was 16,25 inches in greatest total length. The problem is the skull was measured in the wrong way:

" ... Next morning we found the tiger dead, about sixty yards from where he was fired at. I have never seen a finer tiger. He measured 10 feet 2 inches, and must have been an inch or two longer had the tape been put over him before he had got stiff. He was in his winter coat and very perfectly marked. The measurements of his skull as given by Messrs. Spicer & Co., of Leamington, who set up the skin, are in their words 'over the bone' as follows: length - 16,25 inches, breadth - 9,875 inches and weight cleaned 4 lb. 14 oz. ... " ('Jungle trails in northern India', Sir John Hewett, first published in 1938 - I have the 2008 Natraj Publishers reprint, pp. 180).

In those days in northern India, tigers were measured 'over curves' as a rule. My guess is the skull was measured in the same way ('over curves'). Indirect confirmation is in the width and weight of the skull in that it doesn't add up. My guess is the skull was just over 14 inches in a straight line.      

I know a few taxidermists over here. When they have a skull they can't determine, they call me. That should tell you something. I have to add I don't trust measurements taken by taxidermists (and many biologists, for that matter). My experience says that many of them tend to overestimate the length of big cat skulls, especially when they own it (...).

On the other hand. I have seen captive lions and tigers with very large skulls. The facility I often visited a decade ago had a few that could have reached 16 inches. I asked the director of the facility to keep the skulls of his big cats for photographs and measurements. The answer was impossible. When his cats passed away, they had to be destroyed immediately. Law. Our House of Commons is opposed to trade in body parts of protected animals, like tigers. When you have a facility and a license, you're not going to play dice. No skulls to measure, that is. A pity.

A few remarks to finish the post.

Although the longest confirmed Amur tiger skull is 383 mm. in greatest total length, it's very likely that some skulls exceeded that mark. In one of his papers, Per Christiansen published the condylobasal length of three captive male Amur tigers. One of these could have been very close to 400 mm. in greatest total length. Same for the captive Amur tiger from the Duisburg Zoo and the wild Sungari River tiger shot in 1943. My guess is 16 inches (406 mm.) could be about right for the largest males. The 'normal' maximum would range between 375-385 mm. Some skulls of wild Indian (and Nepal) tigers could be close in size and I know of at least one skull from Annam (Vietnam) that, according to Rowland Ward, also reached 16 inches. The longest lion skulls might reach 16,5-17,0 inches.

The main difference is in the averages. My guess is the difference between large lion and tiger subspecies would be close to an inch, perhaps a bit less. When they are about similar in size, tiger skulls often have a slightly wider rostrum and longer canines. Indian tiger skulls in particular tend to be a bit wider (zygomatic width) and heavier. In absolutes, apart from rostrum and canine length, it would be a close call.

What we know, is based on very limited samples. If there's one department where biologists could clear the mist, it would be skulls. Reply