Ottoman Shock Troop Sleeve Badge

[Tom W.]

I recently bought an exceptionally clear period copy of the well-known photo of Ottoman shock troops on the Palestine front in 1918. Most if not all of the soldiers are wearing a badge on the upper left sleeve. On further examination the badge has two tassels hanging from it. Someone told me that these tassels indicate a courier or message runner, but would an assault unit really have so many couriers?

Looking at German organization, there was usually no more than one message runner per company; the Turks based their assault units on the German model. My photo depicts a platoon, not a company, and every badge visible has the two tassels, which are in different colors depending on the soldier.

Could it be a rank badge?