A lack of understanding on your part does not equate to a failure of an entire discipline. It only reflects on your closed mind.
Please Think,
A lack of credible scientific proof on your part does not mean a closed mind on my part. What your remark probably really means is that you don't really know what you believe in. However I will be very open to your explanation and proof of the transition from invertebrates to vertebrates.
Expectant Regards,
Boiler Plate