NewSpecies

This is an artist's rendition of the proposed Scytalopus krabbei, just now confirmed through genetic analysis as a new species -- pending the IOU's final approval-- within the tapaculo group of the perching birds (passerine). They are rarely ever seen, their presence generally only ever made known through their calls, live in the Andes, and have never been photographed alive. The artist is professor Jon Fjeldså of the University of Copenhagen Zoological Museum.  

Gallinago imperialis Pull31Jan2003

In 1983, Danish ornithologist/biologist Niels Krabbe (after whom the bird is named) got a fleeting glimpse of it while on field research in the Andes. He manged to also record its song. And has spent the past many decades working to understand what he had briefly seen and recorded deep within a tropical cloud forest, which is the bird's natural habitat.

aggressive song, 14 secconds

These small birds can barely fly, so they stay close to the ground, foraging in the thick wet cloud jungle undergrowth among rotting logs, roots, mossy rocks, etc. and do a damn good job of hiding and melting into the background when disturbed in the least little way.

The bird's Danish common name will be hvidvinget tapaculo; white winged tapacula in English. Right now, due to the COVID-19 pandemic, all field research is on hold, as is a lot of the deeper research at the U. of Copenhagen and "paper work" peer review from the IOU (International Ornithologist's Union).

There are now 10,928 known bird species on this planet. 

But the current rate of bird extinction, despite a recent small drop in that rate due to conservation measures in recent years, points to the theory that we are currently in the midst of the 6th mass extinction crisis since the relatively sudden evolution -- hence, Cambrian Explosion -- of most major groups of animals about a half billion years ago.

With exceptions, such as with crows, seagulls and sparrows who can adapt to some human activity, most birds are exceptionally vulnerable to disturbances and pollutants in their habitats.  Remember the DDT crisis of the 1960's, when the bald eagle was threatened with extinction?  I played an insignificantly small part in that work as an undergraduate research assistant atFSU's wilderness bird lab, under department chair, professor of ornithology, Frederick Davis. Birds' basal metabolic rate, and thus need for energy, tend to be relatively quite high among animals of their equivalent size, partly due to the demands of flight, and a respiratory system that include lungs that don't expand and contract like a mammal's, and hollow wings that not only enable flight but also help with the oxygen-CO2 exchange of respiration.  Imagine diving from a great height at over 320 KPH (200 MPH) and trying to breathe.  That's what evolution "designed" a Peregrine falcon to manage. 

Because all observations of the Scytalopus krabbei describe it as entirely dependent on a very specific ecosystem at ground level -- old growth, dense, dark, wet, cloud forests at high altitudes close to the equator for warmth -- any sort of human intrusion... logging, mining, urban expansion etc... would spell the bird's almost immediate local extinction. From the preponderance of all relevant evidence, birds that evolve within such very specific ecosystems play critically important roles in that ecosystems stability.  And since it is a peek-a-boo bird, now you see it, now you don't, just exactly what role Scytalopus krabbei plays in that dense jungle undergrowth is mostly for now a lot of intelligent guesswork, but also based on the work that has been done by Dr. Krabbe et al on the bird's closests cousins in the Andes.  That work is on indefinite hold due to the pandemic.

The point here is that these wildernesses are critically important to the planet's, and thus humanity's, life support system, the biosphere.  It is an incredibly complex system to model, all the planet's ecosystems from the ocean depths to high up in the atmosphere are integral to it, but the pressures to understand anthropogenic climate change because of how it threatens our civilization and our very existence has significantly demystified it.

I bring in a bit of avian anatomy and physiology simply to underscore how very vulnerable they can be to a lot of human activity.  The complexity of their respiratory system, which began evolving from out their dinosaur predecessors during the Jurassic about 150 million years ago (it's much more complex, click here for the simple on that) leaves them wide open to many issues that humans might better tolerate. DDT was one example.  But that had to do with the chemical's capacity to concentrate as it went up the food web from insects towards apex birds such as eagles, where it inhibited calcium layering on developing eggs.  There is a group of molds, Aspergillosis, which is found just about everywhere that there is human activity.  We are pretty much immune to most of their spores.  But birds that have evolved in isolated ecosystems, such as this, can be highly susceptible to devolloping fatal pulmenary diseases from fungal species to which their immune systems are unacquainted.  As we bring in machines, non-indigenous human settlements and industry into the Scytalopus krabbei's cloud jungle habitats, with their volumes of contaminants, the impacts can be, well, astronomical.

avian breathing

A mammal's lungs are made up of millions of tiny balloons, called alveoli, which expand and contract as the animal breathes. A bird's lungs, on the other hand, are not elastic - they do not change size when the bird breathes. The bird's lungs are composed of air chambers whose walls are made of a thin layer of squamous epithileum surrounded by capillaries. Specialized elastic structures called air sacs are connected to the lungs and act like furnace bellows to draw air through the lungs - very much like a furnace forces air through the ductwork of a house. As air passes through the ductwork of the lungs, oxygen in the air is exchanged for carbon dioxide in the blood of capillaries winthin the chamber walls.

The bird has two sets of air sacs. The caudal air sacs include the abdominal air sac and the caudal thoracic air sacs. The cranial air sacs include the cervical air sac, clavicular air sac, and the cranial thoracic air sacs. Air sacs even extend into the bones. When the cavity of a bone is at least partially filled with an air sac, the bone is said to be pneumatized. Birds who fly have a more extensive system of air sacs, including the pneumatization of more of their bones.

Compression or expansion of the air sacs occurs when the size of the body cavity in which they are housed changes. Cavity size is controlled by muscle movement. The largest of the air sacs, the abdominal air sac, lines the inside of the abdominal cavity and surrounds the abdominal organs like a coat. As a bird becomes more active, it requires more oxygen. Increased movement forces a greater degree of compression and expansion of its body cavities, and in turn inflates and deflates more of its air sacs. This not only forces more air through the lungs, but also makes the bird's relative weight lighter. When a bird takes off for flight, the exaggerated movement of its wings creates an air current which fills its air sacs, including those within its bones, and makes the bird light enough to fly. The air current created is referred to as "flight wind". The abdominal muscles are largely responsible for breathing while at rest.  --University of Illinois at Urbana–Champaign

Bent Lorentzen

Bent Lorentzen

This email address is being protected from spambots. You need JavaScript enabled to view it.
Recent Articles
The Queen of Denmark Screwed Up Royally
Really Cool New Dinosaur with Feathers Discovered
Star Spangled Banner
What the Coronavirus Can Teach Us
Mr. Tangerine Man

  • No comments found