Gibson and Walk- Alternative Evidence

Supported- Lashley
1)Rats reared normally&in dark both jumped a gap accurately-suggesting innate perceptual skills.
2)Supports as both found that dp is innate, both concluded that this ability in adaptive and passed on by evolution.
3)Lashley trained the dark rats before testing them, blurring nature and nurture- so weaker.

Supported- Yerkes
1)Aquatic turtles have poor depth perception compared to land as they have evolved-cant fall in sea
2)Supports as 24% of aquatic turtles crawled to deep side as they had poorest dp of all pps
3)G&W used a wide range of pps including different animals whereas Y just used turtles.

Challenged- Campos
1)Older infants showed much more fear that younger infants-learned not innate. Infants are more likely to go to deep side if mothers facial expression is welcoming not fearful, which again suggests learning.
2)Challenges as G&W says dp is innate whereas C says it comes with experience.
3)G&W included a wider range of pps including newly born animals which made it a fairer test.