The Giant Shipworm

When it comes to mollusks, people talk a lot about the charismatic giant squids and giant clams (and for good reason!), yet, to my mind, these are not the strangest—or even the most elusive–giant mollusks. Scientists have long sought a very different creature—the giant shipworm (Kuphus polythalamia)—which they knew from its bizarre meter long tubal shell. Yet despite the fact that such shells were (relatively) plentiful—marine biologists never found a living specimen…until this spring, when internet clips revealed footage of people eating huge shipworms in the Philippines. Researchers were thus led to a remote lagoon in the archipelago where at last they discovered living giant shipworms flourishing in the foul muck. What they then discovered was the most shocking thing of all…

But first let’s provide some context. Shipworms are bivalve mollusks (like clams, oysters, and mussels) which eat wood–a surprising amount of which finds its way into the oceans. Wood is extremely difficult to digest, since it contains lignins, cellulose, and such like tough organic polymers. Shipworms digest wood the same way beavers and elephants and termites do—with help from symbiotic bacteria. This made shipworms the bane of pre-industrial mariners (who counted on intact wooden hulls in order to remain alive).

But shipworms are small, and the giant shipworm is…giant. The fact that the giant shipworm is an insane 130 cm long cylindrical clam with a gun metal blue body and obscene flesh gills which lives in a huge calcium tusk the size (and shape) of a baseball bat is not at all the strangest aspect of the creature. What is most odd about this mollusk is how it eats: it doesn’t. The foul anaerobic slime at the bottom of that lagoon in the Philippines is rich in hydrogen sulfide from decaying organic matter.

The giant shipworm doesn’t eat this decomposing matter (indeed, its mouth is all but vestigial). Instead it has bacteria in its gills which live upon hydrogen sulfide. The giant shipworm survives off of the byproducts of this bacterial respiration. It grows huge off of toxic gas. This strange metabolic cycle is of great interest to scientists for what it reveals bout symbiosis, adaptivity, and metabolism. Perhaps someday it will be useful as well. Maybe future generations of explorers will love giant shipworms for their ability to live on waste product gases just as much as vanished generations hated shipworms for eating ships.

Luzon Bleeding Heart Pigeon

Is there such a thing as a Gothic pigeon?  There are a lot of different breeds of pigeond, however the most Medieval-looking member of the Columbidae family was never shaped by human selection. The Luzon bleeding heart pigeon (Gallicolumba luzonica) is a delicate shy bird which lives in tropical forests of Luzon, the largest island of the Philippines.  The birds eat berries and grubs of the forest floor, which they almost never leave except when they are nesting.  They are a mixture of barred gray above and cream color below, except for their distinguishing feature, which sets them apart from all other birds.

Gallicolombe poignardée. Famille des Columbidés. Ordre : Columbiformes

Bleeding heart pigeons have a group of scarlet feathers at the center of their breast which make it look as though they have a terrible bleeding hole in their chest.  In female birds this feature is somewhat subdued, however in males it glows incarnadine like a lurid painting of a Christian martyr.  Male birds even appear to have droplets of blood running down from the terrible heart wound.

The first time I encountered this bird was not in a book (or on a random blog written by some weirdo), but in the Bronx zoo.  I saw a glimpse of a male bird at the back of an aviary and I got all afraid that he had been horribly hurt.  Only when I saw the picture on the exhibit were my fears assuaged.  All of this leads up to the question of why these animals look like they have been shot through the heart. There are lots of folklore explanations (of the dogwood religious just-so story variety), but the real answer is that nobody knows. It is a shockingly metal look for such an unassuming and modest bird.

Sadly the bleeding heart pigeon is growing scarce as its forest home is cut down and made into plywood. Additionally, people capture and sell the birds into the pet and aviary trade. Like the planet Jupiter, it is valued for its lovely and unnerving red spot. With its mild nature, endangered status, and religious martyr good looks, perhaps the bleeding heart dove is a perfect mascot of the terrible plight of animals in our over-burdened Anthropocene world.

The Palawan Peacock-Pheasant

Male & Female Palawan Peacock-Pheasants (Polyplectron napoleonis) Photo by René Lausberg

Just in time for the holidays, here is a colorful fancy fowl to enjoy! The Palawan peacock-pheasant (Polyplectron napoleonis) lives in the humid rainforests of the Palawan islands, a small chain of islands which are part of the Philippines and which are located in the Sulu Sea (to the southwest of Manila and just north of Malaysia).  If you count their splendid tails, male Palawan peacock-pheasants grow to be a half a meter (18 inches) long.  Females are much smaller and plainer.  The pheasants voraciously hunt the many invertebrates which live in the jungle and they live on a varied diet of insects, myriapods, mollusks, spiders, and isopods as well as smaller vertebrates such as frogs, lizards and baby snakes.  They also eat some berries and seeds.

Male Palawan Peacock-Pheasants (Polyplectron napoleonis)

In a world of beautiful birds, the male Palawan peacock-pheasant stands out because of his black plumage, his svelte eye mask, his erectile crest, and above all because of the large iridescent green-blue ocelli on his magnificent tail (which he can fan above himself in the manner of a peacock).  From an earlier post, you will recall that ocelli are ornamental “eyes” made of feathers.  The birds are monogamous—which is to say they form tightly bonded pairs which look after the nest together.

Male Palawan Peacock-Pheasants (Polyplectron napoleonis)

Sadly, peacock-pheasants are tropical birds which do not take well to aviaries and bird farms.  The species is listed as “vulnerable” because of the swift deforestation of the Philippine jungles and because of overcollecting of the magnificent feathers, however the Palawan peacock-pheasant does not seem to be very likely to go extinct soon—which is splendid news for bird-lovers and aesthetes!

Male Palawan Peacock-Pheasants (Polyplectron napoleonis)

The Rainbow Eucalyptus

Rainbow Eucalyptus (Eucalyptus deglupta) photo from Flickr by See Reeves

Only 15 species of Eucalyptus trees occur naturally outside of Australia and of these 15 only Eucalyptus deglupta made it to the northern hemisphere without human help.  Eucalyptus deglupta is native to the lowland rainforests of Papua New Guinea, Indonesia, and the Philippines. The tree grows rapidly to 75 meters in height (about 250 feet) which makes it one of the world’s giants.  Sometimes it becomes so large that it grows 3-4 meter tall buttresses to help it support itself.  Because of its rapid growth, large size, and medium-strength, slightly lustrous wood, these eucalyptus trees are grown commercially in huge monoculture plantations for pulping into paper.

 

Rainbow Eucalyptus (Eucalyptus deglupta) photo from Flickr (http://www.flickr.com/photos/amelia525/303048913/) by *amelia*

The most remarkable aspect of this huge useful tree is its remarkable bark color.  The tree sheds long strips of bark throughout the year which exposes greenish yellow inner bark.  The exposed stripes of green then change color to orange, purple, red, maroon, and dark green.  Since the tree is constantly shedding narrow strips of bark its trunk becomes dazzling vertically striped rainbow of lovely colors.  In wet tropical gardens around the world the Eucalyptus deglupta is grown as an ornamental highlight both because of its beautiful color and impressive size.

Close-up of Eucalyptus deglupta