Check the thread https://www.google.co.in/webhp?sourc...rhinos%20india
There are numerous other sources for on this.
The lack of signs of horses (though it was mentioned in epics and puranas in many places) has been the one last point the believers were sticking too with the hope to continue to believe that native Indians are different and inferior race and aryan (superior race) brought all knowledges and horses along with them somewhere from wilderness in eurasia !!
Still there will be cynics and people who do not want to believe that India was a superpower of knowledge, commerce and good governance even in distant past.