It depends on the 'sighting method' used by the robotic guards, the nature of the weapon, and the already available genes in the animal population.
There is a very big difference between 'natural selection' and 'genetic evolution'.
If, for instance, the robots use infrared, then if there were already a gene in the animal population that reduced the infrared footprint (thicker insulating fur, more capillaries in the belly than the back, heat dissipated by paws on the ground, heat dissipated by vapor from the mouth - therefore the IR footprint was not the center of mass but in front of the center of mass, leading to targeting inaccuracies) then over time these genes would be 'selected' and thus the animals that had these genes and survived would result in a greater representation of these genes in the population, and in turn a greater probability of survival.
Or if the weapon were laser, did this animal already have a gene in the gene pool that produced in some animals a fur or skin that was more reflective to the laser (like pigment in the skin allows some people to stay out in the sun longer)?
But if the animal species did not ALREADY have a gene in the gene pool that produced some trait, skill, or factor that resulted in superior survivability to the robotic guards, then there is no trait that can be selected for. At that point, it is a crap shot that some random gene mutation might result in a greater survivability factor, and that mutation actually survives every other hazard to being reproduced, and that gene's 'offspring' live to reproduce. But that hope rests on ONE individual surviving long enough to reproduce. Unless you believe in 'evolution by intelligent design'.
That's what extinction events are all about. Failure to already have a suitable gene in the gene pool in sufficient numbers to assure enough survivors.