Clubbing is an enlargement of the ends of the fingers and a downward sloping of the nails. Although it's not caused by chronic obstructive pulmonary disease (COPD), it can be a sign of coexisting lung cancer or other lung disorders in patients with COPD. Clubbing is sometimes called digital clubbing. It can affect the fingers and/or toes.
Relatives. Darwin's finches can be divided into groups based on beak type. There are three species of tree finch: the small tree finch, medium tree finch, and large tree finch. Tree finches have grasping beaks.
These trees have slender, often delicate branches and thus are not suitable for carrying nests of birds, though many small finches may find a pleasant seat among their leaves. The leaves of the Birch are usually ovate, or egg-shaped, though some subspecies have more triangular-shaped leaves.