Allopatric speciation is just a fancy name for speciation by geographic isolation, discussed earlier. In this mode of speciation, something extrinsic to the organisms prevents two or more groups from mating with each other regularly, eventually causing that lineage to speciate.
The downside of this is that it can only tell if youâve engaged in drug use in that window. For example, if you smoke marijuana on a daily basis but stop 2-3 days prior to your mouth swab test, the results will probably come back negative. It canât detect prolonged use or the remaining presence of a trace amounts like a urine test can.
A urine drug test can detect marijuana as soon as 2 to 5 hours after use. However, the bigger question is how long will it still be detected with a THC urine drug test.The length of time marijuana is detected in urine depends on the amount used, frequency of use and the user's weight and body fat.ou can also test for more drugs at a time than you can with any of our other convenient at home drug tests. Despite these advantages, a marijuana urine test may not suit your needs as well as a marijuana saliva test or a marijuana hair test.