Sub-families (1 Viewer)

I am trying to determine the difference in the hummingbird subfamilies that I have seen. This is what I have so far:

HERMITS - Various sizes with stripes on side of head and large downward-curved bill.

SABREWINGS - Large, various colours. Black, downward-curved bill. Broad Tails.

EMERALDS - Straight bills either black or red and black. Males are green, females have white front and a white spot or streak behind the eye.

SCALY-BREASTED - Has a scaly breast as the name implies. Only one bird in this sub family called the Scaly-breasted Hummingbird.

COLIOPE - Only one bird in this subfamily called the Caliope Hummingbird. Has a short bill, green back, whiteish front. Male has red streaks on throat. Female has dark streaks on throat and pinkish sides. Females also have white tips at the corners of the tail.

SHEARTAIL - Small, forked tail. Downward curved bill. Two birds in this subfamily, both in Mexico.

JACOBIN - Large with all-white tails.

GOLDENTAIL - As the name implies, has gold-coloured tail. Only one bird in this subfamily called the Blue-throated Goldentail.

Mangos - no idea what makes a mango different from other hummers. Is it their colourful tails?

Can anyone add more info or make corrections? I am mainly interested in the ones that I have seen. I know that there are dozens of others.

You can see my hummingbird report to San Ignacio Belize at www.mytripjournal.com/findtom4

One problem is that only the hermits constitute a subfamily (Phaethornithinae). The rest are members of the subfamily of typical hummingbirds, Trochilinae. These are the only subfamilies of the Trochilidae that are currently recognized by taxonomists.

Another issue is that taxonomic relationships aren't always obvious to traditional taxonomists, much less to casual field observers. DNA studies are providing evidence that many of our traditional generic groupings don't reflect evolutionary lineages, and it's likely that we'll soon see major changes in the number of hummingbird genera and the species they contain.

Based on recent DNA studies, McGuire et al. (2008) proposed several major groupings within the Trochilinae that may eventually be accepted as tribes. Those with more than one member are the Topazes (Topazini), Mangoes (Polytmini), Coquettes (Lophornithini), Brilliants (Coeligenini), Mountain Gems (Lampornithini), Bees (Mellisugini), and Emeralds (Trochilini). The Giant Hummingbird occupies its own branch of the subfamily tree (Patagonini).

This is how the species and groups you listed fit into the McGuire et al. hierarchy:

HERMITS - Phaethornithinae
SABREWINGS - Trochilini
EMERALDS - Trochilini
SCALY-BREASTED - Trochilini
CALLIOPE - Mellisugini
SHEARTAILS - Mellisugini
JACOBIN - Topazini
GOLDENTAIL - Trochilini
MANGOES - Polytmini

Thank you Sheri. Even if they are not offical subfamilies I would still like to learn the differences in them. For example, a Jacobin is different from a Sheartail. Why is a Green-breasted Mango not called a Green-breasted Hummingbird? I dont want to get too deep into taxonomic rules, I would just like to learn what makes a Mango different from other hummers even if it is not an offical subfamily. Just from a visual point of view and not taxonomic. Tom

Tom, taxonomy is classification, and classification is what you're trying to learn. Unfortunately, English group names are often unhelpful because they derive more from history and culture than science.

Mangoes, all of which are in the genus Anthracothorax ("coal-black chest"), got their English group name in the same way as Sedge Wren, Cactus Wren, and Myrtle, Palm and Pine warblers: Early observers noticed certain large hummingbirds hanging around mango trees. The name almost certainly started out as "mango hummingbird" until related species were discovered, then "mango" was adopted as a group name.

Other group names are less reflective of evolutionary relationships. "Emerald" and "sheartail" are among several English names applied to superficially similar hummingbirds that aren't necessarily close relatives. Hummingbirds called emeralds are found in three genera: Amazilia, Chlorostilbon and Elvira. All 17 traditional members of Chlorostilbon are called emeralds, but DNA evidence indicates that the Blue-chinned Sapphire also belongs in this genus. Eight "emeralds" are in the genus Amazilia, but the other 21 Amazilia are just called "______ Hummingbird." Even more confusingly, the Chlorostilbon and Elvira emeralds exhibit the strong sexual dimorphism that you've associated with the group name, while the Amazilias do not. Of the three "official" sheartails, the Mexican and Slender sheartails are more similar in both appearance and distribution to the Lucifer and Beautiful hummingbirds than to the Peruvian Sheartail; they all seem to belong to the same branch of the bee tribe as the woodstars.

The best way to get a handle on how confusing and inconsistent English names like these relate to scientific classification is to compare members of each genus with each other and members of closely related genera. Wikipedia's list of hummingbird genera is a good starting place for linking English group names to their genera, and the "tree" diagram (Fig. 1) in McGuire et al. 2008 will help you sort out the latest picture of how the genera are related to one another (not all genera are represented, but most of the missing ones are discussed in the text).

OK. I thought that all Mangos must have something in common that made them different from other hummingbirds. Same thing for Emeralds, Sheartails, Jacobins, etc. I see now that this is not the case. The names seemed to have been picked at random. Very confusing. Thank you very much for your help. Guess I will just call them all hummingbirds and leave it at that. Tom

All mangoes do have characteristics in common. That's why they're all placed in the same genus. Likewise the two species called jacobins (genus Florisuga). Some of these unifying characteristics are easily observed (size, shape, plumage, habitat, behavior), some are not (internal anatomy, DNA).

The vast majority of English hummingbird names are descriptive, at least for adult males. The only random-sounding name that comes to mind is Calliope Hummingbird, which doesn't seem to have any connection to either the Greek muse of epic poetry or a steam-powered pipe organ.

What I was trying to get across is that English names are often based on superficial similarities and don't always accurately reflect scientific classification, and that scientific names, especially the genera, are far more reliable as a guide to how they're related to one another.

Sheri has stated most of what there is to say, although I must add that current taxonomic thinking elevates a new, more basal lineage separate from the hermits and the other hummingbirds. This new subfamily includes only four species: the two big topazes and the two jacobins. The second subfamily includes the hermits and sicklebills. The third subfamily includes everything else (bees, emeralds, brilliants, etc).

Carlos

csanchez7 said:

This new subfamily includes only four species: the two big topazes and the two jacobins.

Click to expand...

That was a really surprising revelation. The drab hermits and their allies were widely assumed to be basal to the hummingbird clade, but these results suggest that colorful plumage is the primitive condition for the family and cryptic plumage evolved later.

I've been suspicious about the jacobins ever since I banded my first and discovered that their central upper tail coverts are elongated into a sixth pair of tail feathers (most hummingbird have five pairs of true tail feathers). Odd members of a family full of oddities.

If you know of a Web-accessible revision to the cladogram in McGuire et al. 2008, a link would provide a useful update to these issues.

Sheri,

John Boyd has an excellent track record for keeping up to date with the latest thought processes on this and other bird families:

http://jboyd.net/Taxo/List5.html#trochilidae

The normally very conservative Clements list has followed suit and reordered the hummingbirds, placing the topazes and the jacobins first and the hermits/sicklebills second.

Carlos

Thanks for the link, Carlos - some very interesting revisions even to the tribes proposed by McGuire et al.