Passerines vs. non-passerines
Explanation of the difference between the two orders
As shown in the second-tier header above, bird species are generally subdivided into "passerines" and "non-passerines". What is the difference between the two?
The answer is quite straight-forward, once one knows the Latin name of the common House Sparrow - "Passer domesticus". Passerines are birds that, like the House Sparrow, have three toes forward, one backward, e.g. when sitting on a perch, non-passerines don't. As a rule of thumb, songbirds are passerines, others are not.
But there are some more subtle rules to this. There is also a distinction by the birds' voice boxes (their "syrinyxes"). There are a number of birds that have a passerine foothold, but a more primitive syrinyx than the true songbirds. These are often called "suboscines" (where true passerines are "oscines") or also "semi-passerines". The only examples of this category in Australia are the Pittas.
Passerines |
Non-passerines |
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Example passerine: Brown Honeyeater
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Example non-passerine: Australian Bustard
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Example passerine foothold: Pied Currawong - three toes forward, one backward
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Example non-passerine foothold: Budgerigar - two toes forward, two backward
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