What is one trait that could be used to separate these albatrosses into two groups of two birds each

Large group of solid black feathers vs. Black and gray patterned feathers

Explanation:

QUESTION IS INCOMPLETE. It shows 4 different groups of animals:

Albatrosses are among the largest flying birds, forming a family of large seabirds distributed throughout most of the Antarctic, Pacific and South Atlantic oceans. They have the largest wingspans which allows them to move very efficiently in the air with little effort. They feed on squid, fish and krill, either by picking up dead animals or by capturing their live food at the surface of the water or by diving.

To answer this, we can use the dichotomous key which is a tool that allows the identification of organisms. There are keys to determine animals, plants, fungi, bacteria, protista, protozoa or any other living being; keys that reach the level of species, genus, family or any other taxonomic category. A dichotomous key is based on definitions of morphological, macroscopic or microscopic characters, from which two possible solutions are derived, depending on whether or not they have a certain character, repeating the process of defining characteristics, until the organism in question is reached.

In this example, we should look at the colors and patterns on their plumage and beaks. With that information, we can separate these albatrosses into:

Large group of solid black feathers vs. Black and gray patterned feathers.

it would be heredity

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.