User:Abyssal/Prehistory of North America/DYK/18
![](http://upload.wikimedia.org/wikipedia/commons/thumb/d/d8/Tempskya.jpg/66px-Tempskya.jpg)
- ... that the stems in the pseudo-trunk of the extinct fern Tempskya decayed as the plant matured, leaving a layer of adventitious roots behind?
- ... that the Paleocene Alaskan maple Acer alaskense was described from a fossil leaf that may be atypical for the species?
- ... that of the three described species in the Eocene bulldog ant genus Avitomyrmex, one species is known only from worker caste individuals?
- ... that paleoecologist Heinz Lowenstam discovered that living organisms can produce magnetite within their bodies?
- ... that the Maya archaeological site of Tres Islas in Guatemala has an alignment of monuments that imitates an architectural group at Uaxactun that served as an astronomical observatory?
![](http://upload.wikimedia.org/wikipedia/commons/thumb/9/91/Arthropleura_1914.jpg/55px-Arthropleura_1914.jpg)
- ... that Arthropleuridea is an extinct class of myriapods which includes, at over 2 meters long, the largest terrestrial arthropods that ever lived?
- ... that the extinct fern Wessiea is known from Miocene fossils found at the "Ho ho" locality in Yakima County, Washington?
- ... that the extinct species Cornus piggae has fruits smaller than any other species in the dogwood subgenus of Cornus?
- ... that Obamadon was an extinct lizard that was named after President Barack Obama as a tribute to his "role model of good oral hygiene for the world"?
- ... that the extinct Actinidia oregonensis was the first kiwi relative described from North America?