Tag Archives: gondwanaland

Metatherians (Part 1 of 2): Extinct Megafauna

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Marsupials.

The immediate association most people have with the term ‘marsupial’ is that of fantastical, adorable, fluffy beasts in the far-away magical land of Oz, equipped with built-in fanny packs for storing their tiny, even more adorable, offspring. Bounding, big-eared kangaroos, sleepy koalas, and perhaps a hyperactive sugar glider or a waddling opossum might cross their minds. Not too far beyond this is where the train of thought pulls into its final stop, and suddenly they’re caught up in the romanticism of Australia itself; the sun-baked, tawny Outback scabland, didgeridoo droning in their mind’s ear, impossibly colorful fish flitting about the Great Barrier Reef, and perhaps Hugh Jackman or Nicole Kidman (whatever their fancy) driving cattle across the Northern Territory during The Dry.

While this idealization is all well and good, there is actually a lot more to these pouched animals than what fits on the in-fold of a Qantas brochure.
Marsupials are really bizarre by mammalian standards, and have a rich and relatively unrecognized evolutionary history that spans back 125 million years. This entry is one of two that will be devoted to these weird little creatures, focusing first on their unrealized illustrious past, and then on lesser known representatives of their clan in the present.

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Odd Gymnosperms

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Conifers.

Most of us living in North America and Europe know these as the “Christmas tree” trees. Those of us living in the Pacific Northwest know them as every single goddamn tree in sight. Towering, evergreen, and ubiquitous in environments ranging from temperate rainforest, to rocky mountaintops, to high desert and salty seashore barrens. Many of us with some life science background in high school learned that these are what are called “gymnosperms” (meaning ‘naked seed’), and are not quite like other land plants, in that they do not produce flowers, and reproduce using things like cones and copious amounts of wind-driven pollen. Due to the visibility and familiarity of conifers in our lives, and their vast economic and ecological importance (beyond the scope of being fabulous living room decorations one month of the year), cone-bearing trees like pines, firs, yews, spruces, and cypresses are the only gymnosperms that come to mind for those of us lucky enough to have a rudimentary background in the exciting field of evolutionary botany.

The reality is that a vast range of gymnosperms exist out there. Beyond the tree farm, beyond the city park, beyond the ornamental cedar in the front yard…is an entire world of alien plants that share that prehistoric, familial association with the relatively primitive conifers we all know and love.

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Keas

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The kea.

New Zealand is a place with many faces. A quaint, rural country of farms and adorable accents. Or a rugged and untamed playground for adrenaline-seeking white trust-fund kids. Or that place with the sheep and Flight of the Concords. Or Middle Earth.

But New Zealand, from a biological and geological standpoint, is an incredibly special place. The islands were once part of Australia and Antarctica nearly 100 million years ago. The chunk of land that made up New Zealand split off and traveled along the intersection of two giant tectonic plates, causing the uplift of the snowy Southern Alps and various volcanoes. It’s isolation from major landmasses (Australia is more the 900 miles to the west, nearest Polynesian islands are about 600 miles away) has given New Zealand a set of flora and fauna unlike anywhere else on Earth. It was so isolated, that it is likely one of the last places on Earth (with the exception of Antarctica) to be colonized by humans; potentially as late as 1300 A.D. by Polynesian sailors. Its location in temperate latitudes (roughly between 30 and 50 degrees south) gives it a climate more akin to the Pacific Northwest than to its Australian or Oceanic neighbors. With the exception of some parts of southern Chile, New Zealand is the only appreciable bit of land in the Southern Hemisphere to experience this type of climate, and the completely unique set of biological players give New Zealand an aire of alieness, clouded by the familiarity put forth by convergent evolution.

One such unique biological player is the kea (Nestor notabilis), one member of a small family of New Zealand parrots (Strigopidae) that diverged from their closest parrot cousins around 80 million years ago, when New Zealand separated from the southern supercontinent of Gondwanaland. Keas are found in patches all over the uplands of the South Island, and are the only alpine parrots in the world. Adapting to the harsh-as-hell conditions in the jagged peaks of the Southern Alps, and surviving repeated Ice Age glaciations, has resulted in the evolution of some intriguing behaviors.

Keas are among the brainiest birds around. They are incredibly social, living in tight-knit groups of about thirteen birds. They are capable of working together to solve problems of acquiring food and surviving the harsh winter season. They will even frolick and play with each other in snowbanks (as shown above) in a disgustingly cute display of ridiculous birdy intelligence. Look at that. You can almost hear the giggles and “tee hees.”

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