Taiwan is racing to contain an outbreak of invasive cane toads, which likely escaped from a black market breeder.
Scientists warn that increased space exploration raises the risk that alien organisms will invade Earth and that Earth organisms will invade other planets.
Experts believe that the spiders, which arrived in 2014, could spread across more of the southern U.S.
A "murder hornet" nest in Washington had 113 adults and 1,500 developing Asian giant hornets inside.
An invasive and destructive "murder hornet" has been spotted in Washington state for the first time this year, and the alien-looking insect was behaving accordingly — attacking a hive of paper wasps.
An invasive species is a type of animal, plant, fungus or any other living thing that has arrived in a new environment and can harm other species there.
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