In the process of forming amber resin drops, sometimes some unlucky insects or other small animals are imprisoned in them, freezing their lives in this moment.
The existence of reproductive isolation, so that these situations can not occur, even if there are some individuals of different species sometimes complete the mating, but they generally can not produce offspring, or produce offspring can not continue to reproduce
Researchers believe that the longer a female fly killed by a fungal infection dies, the greater the spread of these fungi, releasing more chemical signals