Hello everyone, I am Chen Ting, who has loved animals (but not flies) since childhood.
Méng, to hear this name is very domineering, indeed, the thief is because of its "notorious" predatory habits and got the name of a "pirate" word. It is an out-and-out predator, and the means of predation are fierce, they can ambush or catch prey in flight. Once they catch their prey, they will inject saliva containing neurotoxins and proteases into their prey through a short, thick beak, so that the prey is quickly paralyzed and the inside of the body is slowly digested, so that the flies can directly absorb the nutrient solution.
Above: Enjoying a thief in a good food (Image: Wikipedia)
As the name suggests, they feed mainly on insects, including other flies, beetles, butterflies, moths, ants and so on.
Above: A butterfly-eating thief (Image: Wikipedia)
The burglar refers to more than 7,000 species of animals in the family Carnivorous flies , found on all continents except Antarctica , with strong , prickly legs , a pair of large compound eyes , and 3 single eyes between the compound eyes.
Above: Close-up of the pirates (Image: Wikipedia)
So the question is, what magic weapon does such a powerful predator rely on to catch its prey? Recently, scientists have studied the eyesight of thieves, and the results have been surprising. Trevor J. Wardill et al. of the University of Cambridge published the findings in Contemporary Biology.
Our vision system allows us to quickly identify and intercept moving objects, and when the object is far away, we can construct its moving orbit based on the object's relative position to the frame of reference. This is the constant azimuth (CBA) model. Scientists have discovered that a small type of bandit (Holcocephala fusca) relies on this model to achieve aerial pursuit, and also shows a novel forward-looking strategy - "radar locking". When the prey is within 29 centimeters of the burglar, it will lock on to the target, change the speed and orientation, and capture the prey in one fell swoop.
Above: A thief with extraordinary vision (Image: Wikipedia)
It is hard to imagine that this little head can complete such a difficult task, and even the scientists who study it lament: we know that the eyesight of the thief may be better than that of other flies, but we did not expect it to be so good!
Not only that, in order to further explore its vision, scientists have placed some beads in the natural habitat of the thief,
The beads are connected to fishing lines that can be fired, and the flight speed of these beads is controlled by a stepper motor, and two high-speed cameras are used to capture the reaction of the thief when he sees the flying beads, and to construct a three-dimensional pattern of the thief tracking the flight path of the beads. It was found that the distance vectors of these flight trajectories were almost identical when the beads flew at the same speed. Another interesting finding is that the second half of the trajectory of the thief tracking the prey is significantly curved, because the thief is getting closer and closer to the target, and without changing the course, it may collide head-on, so the thief slows down, changes direction, and intercepts the target in one fell swoop. Have to lament the exquisite strategy of this little bug.
Above: The thief tracks the bead's flight trajectory, with the second half bent significantly (Image courtesy of A Novel Interception Strategy in a Miniature Robber Fly with Extreme Visual Acuity)
In addition, scientists have also found that this small insect with a body length of only 6 mm can see objects smaller than 2 mm away from 100 times its body length. Had to sigh again for its extraordinary eyesight.
In this way, if you want to catch a good hunt, it is not possible to have a good skill, like a full meal is not easy.
Here's the Corn Lab, a daily tabloid from school.