I watched the most amazing documentary earlier on National Geographic. About a 3 year old male lion, who killed 40 odd people over a 18 month peroid. If you can try and catch the repeat of the show, "Hunter Hunted". Heres a link you can read more!
3 year Old Male Lion Kills 49 people in 18 Months
Tabs, it was more a combination of the Two like you said the enormous number of railway builders spread along the line and illness due to the tooth decay.
Thanks Sylvia and Ninfapaola - it appears that the lions were possibly in the 'too sick' category as dentition problems would have caused them to look for easy kills - the easiest being humans of course, as we cannot run fast enough, jump high enough or hide well enough to evade them!
Another good read about the Tsavo maneater is "Ghosts of Tsavo; Stalking the Maneater" by Philip Caputo.
The artical mentions the lion had a large absess under one of its molar teeth, which was broken in many pieces. That can set to man eating.
Study of the skulls of the lions of Tsavo reveal that the first lion killed, had a broken right canine tooth on the lower right, the upper right incisors were super-erupted, the upper right canine was rotated and turned inward. Three lower incisors were missing.
As for the broken lower canine it shows massive wear on the stump of the broken canine. The hollow chamber of the tooth is enlarged.
This lion was limited in the effectiveness of the lion's pricipal stabbing and grabbing theeth on one side of the mouth. In addition it would have experienced excrusiating pain with any pressure on the tip of the broken canine.
Teeth damage seems to be one of the major reason in resorting to man eating. It has nothing to do with being maneless.
If you are interested in it, I recommend Bruce B. Patersons book "Lions of Tsavo." It tells you all, based on science about the lions of Tsavo, the Mfuwe lion and more. It gives great insight as to the why.
I would have thought that a male lion having no mane would be an advantage to it's ability to hunt game - as females are much more succesful, partly because the lack of a mane helps them to blend into the environment.
My opinion is that this is a co-incidental fact. Males who are old, sick or who (for some reason) cannot find any game to hunt will take out humans as a 'last resort'.
The lions in Tsavo were possibly in the category of having no game to hunt - as the huge size of the population of the railway builders - and the noise that they generated - would probably have caused the game to leave the area
Once a hungry, and desperate, lion has eaten (and acquired a taste for) human 'meat' they might well continue to hunt humans in preference to game as we are much easier to catch than antelope are!
Now the weird thing about this 3 year old male lion, is that it had no mane!! Why? Another weird thought is that the 'Tsavo Maneater Lions',these lions became infamous around the world for their attacks, (both males) also lacked manes! So all three of these man-eaters had no manes, co-incidence?