Words that flow...

travelingcolors:

Canals of Burano, Venice | Italy

Photo taken by me (Nacho Coca)

(via travelingcolors)

theparisreview:

“But all this world is like a tale we hear -
Men’s evil, and their glory, disappear.”

― فردوسی, Shahnameh: The Persian Book of Kings, completed by Ferdowsi on this day in the year 1010.

rhamphotheca:

“But… where do you get your protein?”

(via: TheHappyHerbivore)

biomedicalephemera:

aspidelaps:

biomedicalephemera:

The Juvenile Hoatzin (Opisthocomus hoazin)

It should first be noted that all birds are dinosaurs (order Saurischia, clade Theropoda), not just descendents of dinosaurs - modern genetic analysis strongly supports this cladistic organization. But given what we’re too often taught in schools, birds and dinosaurs are hard to reconcile in many peoples’ minds.

The juvenile hoatzin, however, makes it easy to see the reptilian traits that once dominated the early birds, and displays the unused genetic codes that lurk in the genome of modern avians. When they hatch, they’re equipped with lizard-like claws in front of their wings. Their use is described here, but in short, they use them to return to their nest and avoid predators. Their claws disappear by the time they leave the nest, having grown together into the metacarpals that support the wing structure.

Another fascinating trait of the hoatzins is their vegetarianism and their digestive tract. They have gut flora and fermentation similar to ruminants, which no other bird has. This is actually what leads to their being called “stink birds” - they exude a lot of stench with the fermentation process. The gut fermentation is so important to the hoatzin that the flight muscles attached to their keel are significantly reduced, to allow for more space for the stomach. They are weak flyers because of this. After a large meal, an adult hoatzin can spend up to two days doing almost nothing, allowing the leaves and greenery to have their nutrients released by their symbiotic gut flora.

Images:

Top: Attitudes of the juvenile hoatzin while climbing
Second row, left: Hoatzin nest with two eggs - Note proximity to water
Second row, right: Two hoatzin chicks preparing to dive, after appearance of threat from above
Third row, left: Hoatzin chick demonstrating strong swimming abilities
Third row, right: Hoatzin chick demonstrating poor locomotion on land
Bottom: Detail of hoatzin chick climbing, using neck, feet, and claws.

Tropical Wild Life in British Guinea, Vol 1. Curated by William Beebe, 1898.

It should be noted that the claws of Hoatzin are not actually simply because they are related to dinosaurs. Their claws actually re-evolved independently - they are not evolutionary leftovers at their core. While it could be considered a re-appearing gene because of their evolutionary history, it’s still something that would have to be selected over time and could have vanished again just as easily, not to mention it’s very unlikely (and impossible to prove) that it is the exact genome coming out of dormancy.

It’s more similar to dinosaurs when one thinks about convergent evolution than when one thinks about descendence, even if they are descendents too.

All of this is true, but I still like the hoatzin as an example of how to start to show people how birds really *are* dinosaurs - it’s a concept that many people don’t even begin to accept easily.

Hoatzin claws aren’t so much elongated talons-turned-wings like the Archaeopteryx seems to have, as they are a set of hooks on the front of a “chicken wing” structure. Note too, that Archaeopteryx and the hoatzin are not closely related at all (also the archaeopteryx may not even be a bird or bird relative/ancestor, but that’s a whole different matter).

Either way, the hoatzin (btw, if anyone’s wondering, that’s basically pronounced “Watsin”) is an interesting bird. The morphological changes in the wing bones as it matures are interesting enough, but the fact that it’s got such a weird digestive system are what really intrigue me.

It should be noted that while the hoatzin is a poor flyer, it’s not because it’s “primitive” or anything - it’s completely because they have a huge gut, and smaller flight muscles because of that. While their gut is a characteristic that some pretty ancient ancestors of theirs had (at least back to the Eocene), the species as a whole isn’t some evolutionary throwback, like some of the Crocodilians. The “hook-hands” of the hoatzin are relatively recent developments, as was noted. But their morphological similarities to the extinct Therapods still helps to remind people that dinosaurs and birds aren’t so different, after all.

theanimalblog:

Two Great White Pelicans clean their plumage in their enclosure in the Frankfurt Zoo.  Picture: Nicolas Armer/AP

cavetocanvas:

Paul Sérusier, The Wash in a Large Meadow, 1894

gastropost:

Gastroposted via Instagram: “After being deprived for 2 months…the wait is finally over…” by @vhycheng | http://instagr.am/p/Wf47dEL5ZA/

cavetocanvas:

Paul Sérusier, The Youth of Queen Anne, c. 1904

hotbritishmen:

As requested: danisnotonfire and amazingphil from YouTube. 

This is the first and last time with these guys because… they seem to dress up like this a lot:

And maybe I’m too old, but I don’t get it.