Which group has the smallest dispersal distances a) Seaweeds
b) Fish
c) Crabs
d) Marine Snails

d) Marine Snails

Explanation:

Marine Snails has the smallest dispersal distance because of their slow mobility and stick to one place. These marine snails have very limited mobility when they are adults and spend their majority of lifetimes in a small geographical area. Dispersal distance refers to the distance a species can move from an existing place or population or the parent organism. According to this definition we can say that marine snails have the smallest dispersal distances.

if the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.