Many species of Arctic and temperate regions are strongly migratory, but tropical birds are often resident, or move only in response to rainfall patterns.

Some of the Arctic species, such as the little stint, are amongst the longest distance migrants, spending the non-breeding season in the southern hemisphere.

The smallest member of this group is the least sandpiper, small adults of which can weigh as little as 15.5 grams (0.55 oz) and measure just over 13 centimetres (5 inches).

The largest species is believed to be the Far Eastern curlew, at about 63 cm (25 in) and 860 grams (1 pound 14 ounces), although the beach thick-knee is the heaviest at about 1 kg (2 lb 3 oz).

However, the classification of the Charadriiformes is one of the weakest points of the Sibley-Ahlquist taxonomy, as DNA–DNA hybridization has turned out to be incapable of properly resolving the interrelationships of the group.

Shorebirds is a blanket term used to refer to multiple bird species that live in wet, coastal environments.

In polygynous species, where one male individual mates with multiple female partners over his lifetime, dimorphisms tend to be more diverse.

Bigger males tend to have greater access (and appeal) to female mates because their larger size aids them in defeating other competitors.

For example, depending on the food available in a shorebird specie's respective niche, bigger bill sizes may be favored in all individuals.