Furthermore, they show that in both aspirated and unaspirated stops, VOT is shortest for bilabial stops and intermediate for alveolar stops, with the exception of the unaspirated stops in Tamil and the aspirated stops in Cantonese and Eastern Armenian.
According to Cho and Ladefoged (1999), there are two ways of considering this: firstly, the cavity behind the velar stop has a smaller volume than that behind the alveolar or bilabial stops; secondly, the cavity in front of the velar stop has a larger volume than that in front of the alveolar or bilabial stops.
If the articulatory velocity is the primary physiological factor for the voice onset difference, we would expect that the VOT would be shorter for apical alveolar stops than for either bilabials or velars, which is not the general finding.
Because the velar stop has extensive contact between the tongue body and the palate, there is a larger Bernoulli force so that the change in cross- sectional area is relatively slow compared with that for the bilabial or alveolar stops.
In print, I use a typeface with marked serifs for dentals and an austerely sanserif one for alveolars.
Emeneau demonstrated that this palatalization could also be blocked by a following alveolar in Tamil-Malayalam, but not in Telugu.
However, a critical problem, and the one relevant here, concerns the two contrasting taps, "dental" /r/ and alveolar /r/.
3) The alveolar tap /r/ seemed to be just that, a single quick tap on the alveolar ridge [r].