Answer:
The similarities in the way barchan and hooked spit forms are:
First, they are formed from sediment or sand movement.
Second, this movement makes them have a peculiar curved form that provides them their major characteristic.
Explanation:
First of all, barchans are sand formations that are created after the accumulation of sand in a place is moved by the wind and provides them a curved form. However, they exist only out of the sea.
Second, hooked spits are formations that happen after sea movement displaces the sediment to create a curved structure that can only exist in the sea. These formations affect the strength and direction of the waves in the sea due to their curved form.
The first reason was that his theory of continental drift was just too weak for most geologists to accept. Even though he believed the supercontinent that broke up into different continents moved, he did not have a clear explanation to how the continents moved. The other reason is that some of his explanation clashed with ideas that were widely accepted in the science communities. He used similar fossils from different continents to back up his theory of continental drift. However, at that time, many scientists that had observed similarities in fossils in places like South America and Africa believed there were similar fossils in different continents because of a land bridge that were formed by two continents.
Many science communities believe that land bridges allowed migration of many different species and even people to one place to another by large bodies of water frozen by low temperature known as ice age.