Answer: alteration of the ecosystem
Explanation:when a new specie is introduced into the ecosystem it may have profound affects in the ecosystem and may also be called an invasive specie.
The affects that it may have on the ecosystem include
1.outcompeting the native specie and sometimes even leading to their extinction because the new specie may be modified in such a way as to have better chances of survival in the ecosystem because of their evolved genetics e.g : the new specie may encounter a native and non evolved specie of the ecosystem and compete with it for survival leading to reduction and even complete eradication of the native specie