Ovenbirds and Waterthrushes

     Ovenbirds and two kinds of waterthrushes, northern and Louisiana, are closely related small birds in the warbler family.  Having come from a common ancestor, probably recently, in geologic terms, these three species look alike for the most part.  And they all spend northern winters in Central and South America where invertebrates are still available to eat.  But there are slight differences among them as well, but differences that are important, particularly in their nesting habitats in the forests of North America.  And as they diverged from their relatives, they became more like birds they are not related to but share habitats with..  The habitats these three warblers nest in with other types of unrelated birds make them more like those birds, not their cousins, an example of convergence.
     Ovenbirds and waterthrushes are brown above to blend into their surroundings on dead-leaf, forest floors.  And they all have light underparts that are liberally streaked with dark, which breaks up their shapes, which is another form of camouflage. 
     Ovenbirds nest in upland woods in most eastern deciduous forests and build nurseries of dead leaves on woodland floors.  Each cradle has a leafy roof, thus the name ovenbirds.  This species looks like thrushes with their large, dark eyes and feather patterns, both walks rather running and stopping as thrushes do.  Male ovenbirds have a ringing, unmistakable chant with the rhythm of "teacher, teacher, teacher".  That song becomes louder as it progresses.            
     Northern waterthrushes and Louisiana waterthrushes have one major,physical difference in their appearances.  The former species is beige underneath while its relatives are white below.  That is a way to identify each species when seen on migration.
     Both species of waterthrushes dance while walking and watching for invertebrates along water, which is a form of blending in.  That bobbing mimics debris bouncing along the shores of woodland streams.  And both kinds of waterthrushes imitate spotted sandpipers that also bob their bodies as they walk along the edges of water in meadows and other open areas to seize invertebrates. 
     Males of both species of waterthrushes have loud songs that can be heard above the music of running water.  And both species hatch young in leafy nurseries on little ledges in stream banks. 
     The reader can see these two kinds of warblers are almost the same in appearance, habits and habitats.  Their divergence comes from where they raise youngsters.  Northern waterthrushes nest along streams and bogs in North American forests, but mostly north of the Great Lakes.  Louisiana waterthrushes, on the other hand, hatch offspring in the same niche, but in woods mostly south of the Great Lakes.
     This is an interesting grouping of related birds because one can see the similarities they got from a shared ancestor.  Yet to reduce competition among themselves, they use different woods and diverse parts of woodlands.  Many other families of life do the same thing to survive.  But the habitats life live in shape them and make them similar to other forms of life that also uses each habitat.