Biology Reference
In-Depth Information
The challenges of the landing and the potential for imminent new discoveries propelled
everyone on the team to begin pursuing their specialties, assisted by graduate students from
The State University of Papua (UNIPA). Steve Richards, the herpetologist, expected a wel-
coming chorus of new frog species. Kris Helgen was eager to see which species of tree
kangaroos and other rare mammals awaited him. Wayne Takeuchi readied his plant presses
for a bonanza of new species. Brother Henk van Mastrigt gathered his butterfly nets. Bruce
focused on birds.
The next morning's first sighting bolstered Bruce's earlier prediction that the Fojas were
probably high enough and expansive enough, and certainly isolated enough, to be a source
of many new discoveries. Right in camp, a bird appeared that looked like a new species of
honeyeater. The black, grackle-sized bird sported a face mask of extensive orange wattles.
When the wattles became engorged with blood, the honeyeater looked as if it were blushing.
The features failed to match any of the species Bruce and Thane Pratt had described or Dale
Zimmerman had illustrated. This unique bird, later named the wattled smoky honeyeater, be-
came the first new avian species discovered in New Guinea in fifty-four years.
The last described bird species in New Guinea had been the long-bearded honeyeater, dis-
covered in 1951 by E. Thomas Gilliard on Mount Hagen, another isolated mountain peak.
Among the vertebrate hunters, ornithologists have now been almost everywhere on the plan-
et. The Fojas may be unique in being uninhabited and untrammeled, but they join many oth-
er tropical mountain ranges in supporting rare species restricted to a single mountaintop or
range. Biological expeditions to other parts of New Guinea and to New Caledonia, the Andes,
Mount Kinabalu, the Eastern Arc Mountains of Tanzania, and the Annamite Mountains of
Vietnam have time and again discovered new species on tropical peaks.
To understand this phenomenon—how species evolved into new forms in mountainous re-
gions—evolutionary biologists and rarity specialists need to summon their inner geologist. In
the Annamites of Vietnam, in Hawaii, in any place of volcanic origin, or where Earth's plates
have shifted, the causes of rarity in tropical landmasses can go back eons.
New Guinea's geologic history is one of great complexity, and the birth of the Foja range
illustrates this point. It all began with tectonic plates, the unevenly shaped floating slabs of
rock that sit under the continents and oceans. Tectonic plates trace back to the early forma-
tion of planet Earth, almost 5 billion years ago, and their motion has been compared to that
of slow-moving bumper cars—colliding, separating, colliding again and remaining stuck to-
gether—with the movements causing the continents to drift. When they collide, new land-
masses arise. Less than a million years ago, ongoing contact between the Australian and Pa-
cific tectonic plates uplifted deep seafloor material. From the collision of the two plates, the
Fojas were born and rose rapidly (by geologic standards) out of the ocean. This uplift be-
came an isolated landmass and attracted mountain-dwelling species from adjacent mountain
ranges. Over cycles of cool and warm climate, mobile species from the high cordillera to the
