Uh, OK Lew!!! the last one
.....
What a beauty though, and I can see why acquiring it would seem as if you had reached the zenith of this excellent grouping.
Every time I look at these distinctly hilted daggers, I cannot help thinking of the chilanum of India, and its anthromorphically inspired hilt form. It is known of course that the trade from India was a constant in the Red sea trade, and interesting to look to the east from India for many sources for influence in Africa.
The interesting hook type end of many of these has also often reminded me of the ceremonial type swords of India which have had this curious right angled blade deviation since ancient times. I think this might be the direction in looking for possible symbolic meaning or influences in these shapes.
Beyond that, pragmatically I have heard the explanation noted by Colin, for hamstringing.
BTW, Colin, I do recall the equally ancient National Geographic article those pictures came from, I think it was about a 1928 issue!!! Fantastic stuff looking through these old magazines, so close to contemporary, and of course these weapons were then, and still are in use.
On another note on the hooked daggers. In conversations with a Beja gentleman from Eritrea, who I came to know quite well over a few years, he told me these were actually used by the Afar (often called Danakil). He still had family in Eritrea, and shared with me a video of the tribesmen using various weapons including kaskaras in dancing ceremonies.
All the best,
Jim