Some biologists believe that the latitudinal gradient in species diversity reflects the fact that high latitudes recently lay beneath large glaciers. if there had been no recent ice age, would we still expect to see a latitudinal diversity gradient?

The enhancement in biodiversity or species richness, which takes place from the poles to the tropics, usually considered as the LDG or latitudinal diversity gradient. It is one of the most broadly identified patterns in ecology.  

If there has been no ice age in the recent time, we would have still witnessed latitudinal diversity gradient as with or without recent glaciation of high latitudes, there is still less energy accessible at high latitudes to encourage diverse biomes.  

he movement of air through earth's or any planet's atmosphere is called wind, and the main cause of earth's winds is uneven heating by the sun. this uneven heating causes changes of atmospheric pressure, and winds blow from regions with high pressure to those with low pressure.

i hope this : )