Possibly it is a response to eating meals and the gas that is from those meals accumulating over the course of the day.Typically the colon is most active first thing in the morning and again after meals. Most of the gas that you had from yesterday is probably gone after the morning increase in activity (and it is quite common to have a BM in the morning). As you eat during the day you feed the bacteria in the colon. Some people over-respond to even normal to less than normal gas production by these bacteria in the colon. It is pretty hard to avoid all gas-producing foods during the day as those include all starches other than rice as well as any number of other carbohydrates.I find that taking probiotics (specifically Probiotica) which should reduce overall gas production limits my end of day farting. Different people will have different symptoms from gas production and the noises and urgency can be from that gas production. Filling the rectum with anything can cause urgency/BM's in some people.If this mostly happens about 1 hour after dinner it could be that most of this is from the post-prandial increase (after eating) in colonic activity. Often the evening meal is larger and heavier and for some people it is the size/volume of the meal that is problematic. (so a larger meal causes a bigger increase in activity)K.