David, how can you tell that it's a male?

You can tell in a few ways. First, the proportions of males and females are different, and usually you can tell just by looking at them (but not always - in photos it often depends on the angle of the shot). Generally males are smaller, more slender, and the head tends to look proportionately larger. Male grasshoppers often have thicker legs (not so much in this species though). Also, in this photo you can see most of the tip of the abdomen; males and females have different parts there. In the male there is a "subgenital plate" that caps most of the lower end and tip of the abdomen (in most genera it makes the end of the male abdomen blunt and rounded, but not in Schistocerca); with a little practice you can learn to see this difference without even thinking about it. In Schistocerca the male cerci are much larger than in the female. In the female the abdomen would usually be longer and thicker, and it ends in four pointed ovipositor valves (for egg laying) that are usually held closely together and make the end of the abdomen look different.

for all the info!

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