The Willow Flycatcher is a small insect-eating bird. The bird has some features which are distinctive. They are darker on the wings and tails, have an indistinct white eye ring with white wing bars, and the breast is washed with olive gray.
They usually breed near water and they live around deciduous thickets. Willow Flycatchers usually travel approximately 1,—8, km between wintering and breeding areas Mark et al. It is distributed in 14 native occurrence discontinuously across Southern California. The species generally grows on sandy oils in low gradients zones, alluvial terraces, as well as on coarse soils on north-face slopes that are in association with chaparral, oak woodland and coastal sage scrub.
This plant species was recognized state and federally endangered in US Fish and Wildlife Service, John Weier and David Herring. Sogge, Mark K. May Retrieved 17 February Biodiversity Atlas of LA. Skip to content. Mammals Perognathus longimembris pacificus Pacific pocket mouse Community: sandy coastal soils Fishes Oncorhynchus mykiss Southern California Steelhead Community: open ocean and in shallow coastal waters The Southern California Steelhead is usually dark-olive in color, shading to silvery-white on the underside.
Unlike other canid species that migrated between Eurasia and North America, dire wolves evolved solely in North America, and they didn't interbreed with coyotes or gray wolves, the study found. The American cheetah stood a little taller than the modern cheetah , with a shoulder height of about 2.
However, the American cheetah probably wasn't as fast: It had slightly shorter legs, which likely made it a better climber than a runner, according to the zoo. Researchers named it Miracinonyx inexpectatus — mira means "wonderful" in Latin, and acinonyx and onyx come from the Greek words for "no movement," based on the false perception that cheetahs don't have retractable claws and claw, respectively, the zoo said.
Inexpectatus is Latin for "unexpected," giving the big cat a name that translates roughly into "wonderful unexpected cheetah with immobile claws. Researchers dated the first known M. They went extinct about 12, years ago. When President Thomas Jefferson learned about a strange claw fossil found in Ohio, he asked explorers Meriwether Lewis and William Clark to search for giant lions during their western trek to the Pacific.
The claw, however, didn't belong to a lion. It was part of Megalonyx , an extinct ground sloth, MacPhee said. Related: Top 10 intrepid explorers. In fact, ground-sloth fossils indicate that these animals began living in South America about 35 million years ago, according to the zoo. Researchers uncovered a 4. During warmer periods, called interglacials, Megalonyx made it as far north as the Yukon and Alaska, MacPhee said.
Megalonyx jeffersonii stood about 9. It survived until about 11, years ago, the zoo reported. The giant beaver Castoroides is mostly known from its fossils in the Great Lakes region, which is "perhaps no surprise for a beaver," MacPhee said. But other fossil finds show the giant lived as far south as South Carolina and in the American Northeast.
Like Megalonyx , the giant beaver ventured into Alaska and the Yukon during the interglacial periods, but retreated south when temperatures dropped, MacPhee said. Castoroides was enormous for a beaver — it weighed up to pounds 57 kg , much larger than the roughly lb. Interestingly, modern beaver remains are found in the same deposits as those of their ancient relatives, suggesting they had similar lifestyles, MacPhee said. Camels that once roamed North America are called Camelops , Latin for "yesterday's camel.
Camelops and its ancestors were no strangers to the states. Fossils show that the camelid family arose in North America during the Eocene period, about 45 million years ago, the zoo said. Most of these species went extinct at the end of the last Ice Age though horses were reintroduced later from Europe , but the coyotes sailed on through. Why is this? How did some species survive while others died out?
This is one of the many mysteries we encounter when we look at the fossil record in the La Brea Tar Pits. Without a time machine, the best way to answer these questions is to study every detail of the fossils we have to piece together the story of what happened with each of these species leading up to their extinction or not. These five particular species are the subjects of a new collaborative research study funded by the National Science Foundation.
With the help of undergraduate and graduate students, researchers will be examining and re-examining tens of thousands of fossil specimens from these five species, taking detailed measurements of each bone, looking at the wear on their teeth, and sampling over individual animals for stable isotope and radiocarbon dating analyses.
In these tests, special machinery analyze small bits of bone collagen or tooth enamel to determine the different ratios of carbon, oxygen, and nitrogen isotopes, which are different forms of these elements. Carbon, for instance, comes in three common isotopes — carbon 12, carbon 13, and carbon The numbers indicate how many neutrons are in the nucleus of these atoms.
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