Did you even read the article you got that from
>In Europe, the spear-thrower was supplemented by the bow and arrow in the Epi-Paleolithic. Along with improved ease of use, the bow offered the advantage that the bulk of elastic energy is stored in the throwing device, rather than the projectile. Arrow shafts can therefore be much smaller and have looser tolerances for spring constant and weight distribution than atlatl darts. This allowed for more forgiving flint knapping: dart heads designed for a particular spear thrower tend to differ in mass by only a few percent. By the Iron Age, the amentum, a strap attached to the shaft, was the standard European mechanism for throwing lighter javelins. The amentum gives not only range, but also spin to the projectile.[19]