Can I measure the body temperature of an ant by infrared measurement technology?
You can aim the IR thermometer at small object such as an ant, but what you measure is an average temperature of the ant & the adjacent surface because the Field-Of-View of the IR thermometer is much larger than the ant. But, if a large collection of ants occupies the whole FOV of the IR thermometer, then one can measure their average body temperature. This FOV is the main consideration to obtaining the correct temperature reading from IR thermometer.