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Heidi Henderson
14,681 followers -
Blue Planet | Explorer in Residence
Blue Planet | Explorer in Residence

14,681 followers
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If you had to write out your diet this week and highlight all the seeds, grains, fruits, nuts and plant-based calories, how much variety would you say you consumed? It appears our earliest relatives consumed a huge variety of plants. A very smart move as some are seasonal and others can become scarce at times. 

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This disarticulated fellow is Mammutus primigenius from the Pleistocene of Siberia, Russia. He's now housed in the Museo Nacional De Ciencias Naturales in Madrid, Spain in a display that shows thoughtful comparisons between the proboscideans. They have a wonderful display of mammoth teeth, the diagnostic flat enamel plates and the equally distinct pointy cusped molars of the mastodons.

He was a true elephant, unlike his less robust cousins, the mastodons. Mammoths were bigger (both in girth and height), weighing in at a max of 13 tonnes. They roamed widely in the Pliocene to Holocene, covering much of Africa, Europe, Asia and North America.

We see them first some 150,000 years ago from remains in Russia. They enjoyed a very long lifespan of 60-80 (up to 20 years longer than a mastodon and longer than modern elephants) and quite surprisingly, at least to me, the last mammoth died just 3,700 years ago in the icy frost of a small Alaskan island.

Not all had the shaggy coat of long hair we picture them with. But all of these behemoth proboscideans boasted long, curved tusks, big ears, short tails and grazed on leaves, shrubs and grasses.

So why the tusks? Likely for displays of strength, protecting their delicate trunks, digging up ground vegetation and in dry riverbeds, digging holes to get at the precious life-giving water. It's a genius design, really. A bit like having a plough on the front of your skull.

#mammoth
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The specimen on the lower right is an approximately 80 million-year-old fossil dinosaur egg from the Late Cretaceous Djadochta Formation of Shahbarakh Usu, Mongolia. It was collected by A. F. Johnson on 17 July 1923 as one of a group of 3 weathered oviraptorid eggs.

The object on the upper left is a water-worn rock, most likely from a river. Its resemblance to an egg is merely accidental.

River-rounded rocks are commonly mistaken for fossil eggs. This is just one method by which nature produces rocks that resemble eggs. Sedimentary concretions are another common imposter.

Concretions often form when some object acts as a “seed” for the deposition and cementation of sequential layers of sediment. On occasion, the matter that initiates the concretion, the “seed,” can be a fossil. To find this out requires cracking or cutting open the concretion.

Genuine fossil eggs usually have an easily identifiable shell which differs significantly from the enclosed sediments either by having a fine surface ornamentation (the smoother the "shell," the less likely it is to be a non-bird dinosaur egg) or a specific type of crystalline structure in cross-section. Also, because eggshell tends to be brittle, the shell is almost always heavily cracked with clear shifting of the eggshell bits.

Ironically, one strong indication against a dinosaur egg identification is a very egg-shaped specimen: most fossil eggs are not "egg-shaped" because most fossil eggs come from non-avian dinosaurs and are everything from spherical to torpedo-shaped.

Additionally, the thickness of the “shell” can rule out an egg ID. Embryos in hard-shelled terrestrial eggs need shells through which they can conduct gas exchange – basically so they can breathe. Past a certain thickness, this becomes impossible.

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Metasequoia (dawn redwood) is a fast-growing, deciduous tree, and the sole living species, Metasequoia glyptostroboides, is one of three species of conifers known as redwoods. It is native to Lichuan county in Hubei province, China.

Although the least tall of the redwoods, it grows to at least 200 feet (60 meters) in height. Local villagers refer to the original tree from which most others derive as Shui-sa, or "water fir", which is part of a local shrine.

Since its rediscovery in 1944, the dawn redwood has become a popular ornamental tree in the Pacific Northwest. We find fossil remains of metasequoia in many of the Eocene sites of British Columbia and Washington State.
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The fossil fish is a nearly complete skeleton from the Britton Formation of the Eagle Ford Shale in Dallas County. Dr. Shimada's study suggests that Pentanogmius fritschi was an active fish in open ocean environments that possibly fed on a variety of small animals like squid and other fish.

https://phys.org/news/2016-02-texas-fish-dinosaur-era-species.html

#paleontology #fossil #fish
#texas


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Fresh, Caged Little Humans. It was a thing.

"Fresh air is required to renew and purify the blood, and this is just as necessary for health and growth as proper food," wrote Dr. Luther Emmett Hold back in 1894.

"The appetite is improved, the digestion is better, the cheeks become red, and all signs of health are seen." Makes sense. I heard my mother tell us to, “go play in the fresh air,” my entire life growing up.

Hold, then a local authority and bit of a celeb when it comes to parenting had recently published his authoritative work, The Care and Feeding of Children. But much like we’ve seen elsewhere in the use of the newly minted US Postal system to mail children... folks in America took his advice and ran with it, interpreting the need for fresh air as a reason to re purpose chicken coops into childcare.

“Well, I never! Who would do such a thing?”

As it happens, Eleanor Roosevelt. You may recall her as America’s longest-serving First Lady.

The lovely Eleanor, wanting to ensure her wee pumpkin Anna, got enough fresh air, purchased a chicken-wire cage back in 1906. She used to hang it out of her New York City townhouse on East 36th Street. Mmm, nice fresh New York Air -- does a baby good.

And you’d think it would stop there. A few eager mom’s eager to try something cutting-edge. But again, nope.

The lovely Emma Read of Spokane, Washington took it one-step further. She applied to the US Patent Office for a new patent on a "portable baby cage." Once fulfilled, portable baby cages became a thing.

You’re welcome.

#history
#parenting
#parenting fail

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Making a Living with your head buried in the sand...

We could call scaphopods the great deniers. They live their adult lives with their heads literally buried in the sand.

A tiny bit of their posterior end sticks up into the seawater for water exchange. Water is circulated around the mantle cavity by the action of numerous cilia. When the dissolved oxygen runs low, the water is ejected through the top end of the shell by contraction of the foot.
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