Over 180 years of theories and estimations have suffered a severe alteration when it was recently discovered that a hummingbird’s tongue uses pumping, not suction when taking in nectar, according to a series of experiments.
Previous to these findings, scientists believed that the colorful and fascinating birds used capillary action to draw their energy source from a variety of plants. The process implied the liquid flowing through the very narrow space and slurping it up even against gravity.
The assumption was first made due to the fact that the bird’s tongue presents itself with two cylinder like grooves, according to lead researcher of the paper and associate of functional morphology at University of Connecticut, Alejandro Rico-Guevara. However, the very slow method did not sound like something a hummingbird would do.
The colorful birds flap their wings up to 50 times per second, hovering above flowers while they’re extracting nectar. They’re creatures of speed and nature ingenuity, so every millisecond counts.
So, the researchers have delved deeper into the matter and set up a type of transparent flowers and cameras able to accurately capture actions at high speeds, and then went on to study 18 hummingbirds species. They ventured from the most common they could find to the most exotic in order to make sure they can make a generalized conclusion.
As it turned out after a while of research and observations, they observed that a hummingbird’s tongue works like a micropump. Once they’re hovering above the flower, their long and slender tongue stands flat up until the moment of contact with the nectar. Once it touches the sweet and energy-providing liquid, their tongue reshapes itself into the cylindrical form and, thus, drawing it in.
The force of re-expansion of a collapsed groove allows it to drain between 5 and 10 drops of nectar per 15 milliseconds, which is about at 100th of a second, according to Rico-Guevara. The capillary action would have slowed their process to four times than the newly discovered quick technique of micropumping the nectar in.
In fact, the recently uncovered manner allows the hummingbirds to lick the flower at a speed of 20 times per second, at an estimated 20 hertz. If the capillary action was used, as previously thought, they would’ve had to lower the speed to 5 hertz. While that would still be quite a speedy run-in with a flower, those extra milliseconds certainly count in the life of a hummingbird.
The study has answered questions, but has also saw to another surfacing. Previous research has concluded that some flowers naturally develop diluted nectar to better lure in hummingbirds, as it makes the capillary action easier. However, if they are using a different method, there must be a different explanation as to what causes certain plants to have higher dilution levels. Further research is still required.