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Tuesday, July 1, 2014

Rudist Colonies: Fun, Wild Index Fossils

     Rudists are some of my favorite fossils, not just because it's a fun word to say, but because they are quite useful index fossils from the Jurassic and Cretaceous:







    Index fossils are the forms of life which existed during limited periods of geologic time and thus are used as guides to the age of the rocks in which they are preserved. John McPhee's analogy from Basin and Range  (1981) describes the concept well:

     "Imagine an E.L. Doctorow novel in which Alfred Tennyson, William Tweed, Abner Doubleday, Jim Bridger, and Martha Jane Canary sit down to a dinner prepared by Rutherford B. Hayes. ... a geologist could quickly decide -- as could anyone else -- that the dinner must have occurred in the middle 1870s, because Canary was 18 when the decade began, Tweed became extinct in 1878, and the biographies of the others do not argue with these limits."

    These marine bivalves were one of the main components of the widespread Tethys Sea between Laurasia and Gondwana about 200 million years ago as Pangaea was breaking up:






     Rudists were one of the main components  of the reefs that formed then:




      Rudists were widespread and had very different shapes making them excellent index fossils for fairly narrow time periods:



     The earlier forms were elongate, with both valves being similarly shaped, often pipe-shaped, while the later, reef-building Cretaceous forms had one valve that become a flat lid, with the other valve becoming an inverted spike-like cone. The size of these conical forms ranged widely from just a few centimeters to over a meter in length.



     Rudists' morphology consisted of a lower, roughly conical valve that was attached to the seafloor or to neighboring rudists, and a smaller upper valve that served as a kind of lid for the animal. The small upper valve could take a variety of different forms, including: a simple flat lid, a low cone, a spiral, and a star-shape.

     The earlier forms tended to be more solitary but the Cretaceous forms were generally more colonial. Rudist colony: they started it millions of years ago. The first naturists died off at the major Cretaceous-Paleogene extinction about 65 million years ago.

     Looking forward to your tales of nudist, er, rudist colonies. ;-)

Indexedly,

Steph
(Word Woman)

Holiday Hummer in the Colorado Mountains 7/3/14 (photo by C. Fiss)




     First clue (these are my photos) to location in the CO mts. See if you can win the geography quiz, at least a bit of a challenge this Sunday morning ;-):


Second clue:


More to come (if needed). Clue number three. Hint: It's very, very clear.





69 comments:

  1. I still have my "Reunite Gondwanaland" tee shirt. ;-)

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    1. Steph,

      I appreciate the map with the Tethys Sea, Laurasia and Gondwana on it. But I can’t find Puzzleria anywhere! Is it on the other hemisphere?

      (Laurasia is actually a kind of nice name for a baby girl.)

      Lego

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    2. You are correct, Scientific Laurasia! Puzzleria was just lurking on the underside of the map, kind of like a slug under a fossilized rudist rock. Thanks for all your efforts to help put Puzzleria! on the map.
      Lego…

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  2. Rudist reminded me of My Fair Lady:

    Every time we looked around, there he was, that hairy hound from Budapest.
    Never leaving us alone, Never have I ever known a ruder pest.

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  3. I'd forgotten that line from My Fair Lady, jan.

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  4. Jan,
    Department of Rude, Ruder, Rudist: It takes some kind of lyrical chutzpah for MFL lyicist Alan Jay Lerner to rhyme “Budapest” and “ruder pest.” It’s almost almost Ogden Nashean:
    “The one-D Bud has hoppy zest,
    The two-D Buddha’s self-possessed,
    But I’ll bet you a wheel of Gouda,
    There isn’t any three-D Budddha.”

    SS,
    I see links between this week’s PEOTS and two recent NPR Sunday puzzle answers: “Set of teeth,” “Colgate,” and now -- the link in PEOTS -- Teethys” Sea! This sea was so named, I understand, because its rudist colonial reefs resembled sets of choppers. Am I mistaken?

    Speaking etymology, Seriously Scientific Steph, what is the etymology of “rudist?” Any connection to “red” and “ruddy?”

    LegoSeeingReeferMadnessRed

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    1. Lego, I like your inventive spirit! I believe the Tethys Sea was named by Austrian geologist Dr. Edward Suess (no relation to THE Dr. Suess who took on the name). But I think THE Dr. Suess and you would heartily approve the sets of choppers origin. I sense a poem you can sink your teeth into coming on..."Ode to a Rudist?"
      As to rudist origins, it's from the Latin, rudis, meaning a slender stick. I don't see a red, ruddy connection...but, yes, creating one works for me!

      Enjoyed the Budddha ditty too.

      Are they now your favorite index fossil too? ;-)

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    2. Here's a three-D Buddha. Please bring cheese to next PEOTS meet-up.

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    3. BTW, it's Seuss, not Suess. And we've all been pronouncing it wrong. Per Alexander Liang, one of his collaborators on the Dartmouth Jack-O-Lantern:

      You're wrong as the deuce
      And you shouldn't rejoice
      If you're calling him Seuss.
      He pronounces it Soice (or Zoice)

      It was his mother's maiden name, German for "sweet".

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    4. Wonderful blues and greys, jan. Saw the Budddha but not sure about the cheese. . .

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    5. Right you are, jan. Dr. Seuss, the author is e before u...and it's Eduard (u not w) Suess, u before e. Ed was a big Alp specialist and Ted (Theodore) Gave us this gem "Spit out every bit of hot air and be careful what you swallow."

      I knew about the Zoice ( didn't you hear my pronunciation? ;-) ) but not about the sweet meaning. Wonder if the geologist's Suess is pronounced to rhyme with deuce.

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    6. SS,

      Is the rudist now my favorite index fossil? Well, let me think a minute. There are oceans to choose from. So, the rudist is not my favorite, not yet, anyway. But it’s in the running, maybe in my top five. And definitely in my top ten. (So many index fossils, so little time!)

      jan,
      I read this New Yorker piece last summer (lots of old magazines cluttering my abode) and enjoyed it much.

      Regarding your three-D Buddha. Did I set you up for that or what!

      Now, if we only had the time, we could speculate on what a four-D Buddha would look like.

      LegoHyperBuddha

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    7. I don't remember that New Yorker piece. But I found this much older book review memorable.

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  5. lego and jan, these are both great Seussian articles. I just liked reading the books. They beat Dick and Jane all to heck. I got in trouble for reading ahead...but nothing ever happened anyway. I spotted that right away. . .

    lego, rudists, rugose coral and ammonites are in my top three for index fossils. I can see where you might be conflicted.

    4-D Buddha must be better than 4-G Verizon service. Not sure what happens with 4-E and 4-F. . .

    Glad to hear your Seussian Voices!

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    1. Buddha would certainly have been 4-D, the Selective Service System classification for "minister of religion, formally ordained by a recognized religion, and serving as a full-time minister with a church and congregation." Is that karma, or what? 4-E was for conscientious objectors, 4-F for those who couldn't meet physical, mental, or moral standards, including those of us on the Group W bench. Sing along

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    2. Great irony, karma, connection there, jan. Great Alice's Restaurant video too. . .now if I could just get 4-G coverage to work reliably in my house! Terrible coverage right here in the big city.

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    3. Your Verizon service must be better than you think. Or your imagination. Or those recreational substances you Coloradans are famous for. I see no video on that Alice's Restaurant link at all, just a still of Arlo's album cover, and the audio track.

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    4. That's what we call a "video" here in Colorado;-).

      Btw, I am still chuckling over the Fallacy of the Beard. I learn something new every day here on the interwebs. . .I think "full" beards are great. Not quite as sold on soul patches.

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  6. This is a fun USGS trek through time in Boston. The Survey is getting cooler every year. Enjoy !

    http://www.boston.com/news/local/massachusetts/2014/07/01/awesome-tool-lets-you-watch-boston-grow-over-the-years/2f5XU9CUMNg8WJUBBLh6qJ/story.html

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  7. A friend helped develop this geography game, Smarty Pins. Enjoy!

    http://smartypins.withgoogle.com

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    1. I like it. Have you tried GeoGuessr? I play that with my niece in CA. But my favorite is Ubi, a board game developed by the same people who did Trivial Pursuit (before they did TP, in fact). It's a trivia game very similar in spirit to Smarty Pins. In fact, I wonder if your friend knew about Ubi?

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    2. Just tried Geoguessr; the instructions are a bit lacking but otherwise it is fun. With both games, it's a little tricky to get the exact location on my Smart phone.

      Yes, he was well aware of Ubi, the board game, and Geoguessr both. I've not played Ubi, though. Sounds like fun.

      Slight preference for Smarty Pins as navigating the roads in Geoguessr on my Smart Phone is also a bit tricky.

      Thanks for the Geoscoop!

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    3. My niece says her AP Bio class played GeoGuessr looking at the flora growing along the road and deciding where that plant grows. Field botany isn't my thing; I just drive up and down the road looking for signs.

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    4. That would be a great way to use the tool. One of my favorite trips was to the Great Sand Dunes in S. CO. My botanist friend told me all about the plants and I told her all about the rocks. This ap reminds me of that. But, looking for signs is a great tip too!

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  8. Cute geologically themed crossword in today's New York Times.

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    1. Liked the Alternate spacing of the clue Mount St Helens as Mounts The Lens, jan. Ash in 12 states including the Source :-)

      Happy and safe 4th PEOTSers!

      Steph

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  9. That's a great hummingbird. Did you really take that yourself? Happy Aphelion!

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    1. A fellow hiker who teaches photography took the photo yesterday...the little hummers are everywhere up here. ;-)

      Our sky was a more spectacular than usual blue yesterday.

      Happy Aphelion to you, jan...and a belated Perihelion (or early) for January 3rd!

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  10. We think the little fellow above is not a Rudist but an adult male Rufous Hummingbird. Have you seen them? They sure do get around.

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    1. Around here, we have the similar Ruby-Throated hummingbird. With those white spots on the tail, are you sure that's a male you've got there?

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    2. No, I'm not sure. According to the locals here "It could be a cross-dresser."

      Are you thinking female or juvenile?

      I am quite a novice birder.

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    3. I don't think I'm up to novice yet. But I keep my Peterson's guide handy.

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    4. My son's good friend is an incredibly serious birder. He hold some record for the most species counted in a single day without using a powered vehicle, or something like that. He starts out at midnight, on his bike, on top of a hill, counting owls I assume, and works his way down to sea level.

      I've always found it curious that birders are allowed to count on the basis of the bird's call alone, without having actually to see the bird. And that it's all on the honor system. Did you see "The Big Year"? It's a, er, hoot.

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    5. I just checked the Cornell U Ornithology site; I think it is a female. Beautiful in any case.

      Did a bit of searching into hummingbirds' hovering motion. Apparently their wing movements are 75 % down movements and 25 % up movements.

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    6. Wait a minute... the wing has to come back up as much as it goes down, or pretty soon the bird will be here, and its poor little wings will be way over there/.

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  11. We just had this same discussion along Clear Creek. Maybe they thrust harder downwards. Wondered if helicopters use the same principle? I know even less about them than birds...

    Interesting about the birders and calls. Do you suppose hummingbird wing sounds count as a "call?"

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    1. Oh, I'm sure they thrust harder downwards. That's the whole point, action/reaction-wise. the upstroke isn't intended to generate thrust, just to get the wing back up for another downstroke. The wing is shaped (and changes shape throughout the flapping cycle) to maximize downward thrust and minimize upward. My point was the ambiguity of that 75%/25% stat. If may refer to the mobilization of muscle fibers, but it's not the amount of movement.

      Helicopters don't flap, at least not while hovering. (Ornithopters are another story.) When hovering, the rotor just spins with a fixed angle of attack, producing downward thrust. In forward flight, though, the angle of attack of each blade is adjusted as it rotates, lower when moving forward, higher when moving back. If it weren't for this cyclic adjustment, the forward sweeping blade would produce more downward thrust than the backward sweeping blade (because of the addition of the forward airspeed), which would roll the aircraft to the left (assuming counterclockwise rotation).

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    2. I don't think a hummingbird's hum has a communication function. It's just 'cause they don't know the words...

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    3. Hmmmmm. Hmmmmm. Hmmmmm. Yeah, I know...My translation of the study was not inspired.

      We are listening to Garrison's show from St. Paul. GK mentioned two of my daughter's friends by name, no humming ;-).

      Headed out for more hummers now.

      May watch The Big Year tonight if it's available. A true for the birds weekend.

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  12. Oh, yeah, different time zone. Here, the sun will be down soon. We used to see bats when we went out for walks on summer evenings, but not for the past few years. I think white nose syndrome pretty much wiped them out around here.

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    1. "The Big Year" was a big hit. Loved all the photos of birds, scenery. Thanks for the recommendation. Prompted renewed interest in birding among my friends though it may need to be "The Big Long Weekend for now."

      The scene with the bald eagles spiraling in the air was extraordinary.

      We saw more hummingbirds late this afternoon and several bats in Denver last weekend. Too bad about White Nose Syndrome your way.

      Tomorrow I plan to post my own version of Geoguessr to see if you PEOTSians can figure out where I was ;-).

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  13. As Brian Jacques told my very young son at a book signing, What do you call a deer with no eyes?

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    1. No idear, you say? Clue number three is above.

      Shifting gears in 97 degree flatland weather. . .

      CPR did a piece on strokes in children, including the fact that the most common time for strokes for juveniles is in utero and may manifest as cerebral palsy. . .



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    2. As he continued, What do you call a dead deer with no eyes?

      Sure, same as with manufactured goods. People and other things tend to fail early in the life cycle due to defects, later from wear and tear.

      Thought you'd appreciate this.

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    3. Your comment from 4:03 on July 2 was oddly somewhat prescient, in light of puzzling things today.

      Thanks for the link.

      Ok, the new photo should help.

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    4. Yeah, I thought of that connection, but I wouldn't want to sidestep Blaine on this blog.

      Still no ideer, really, but if I had to guess, I say Uravan?

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    5. You lost 1000 miles by now. Sorry. But, you can try again ;-)

      Still no i deer, etc. Bison vowels?

      We need a good puzzle more than evvaahh!

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    6. How could I lose 1000 miles? There no place in CO that's more than 400 miles from Uravan.

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    7. Every dead deer joke costs you 500 miles.

      But you can start over. ;-)

      Uraquay quay off.

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  14. OK, if you're not gonna play fair, I'll go with Fairplay.

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    1. Hehe. The latest photo posted above shows the second half of the two words in the town name. Another chemical hint: Spiro.

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    2. OK, looks like Silver Plume, 80476.

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    3. Ding! Ding! Ding! The first PEOTS Geography Quiz Lapel Pin is yours (as soon as they are ready, made of pure Ag, but you [k]new that).

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    4. Don't know why I was sure that second word was "flume"...

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    5. Perhaps you assumed flume because of the old joke about u and me being in word assume (and on the sign) . ;-)

      Naw, I think flume was a reasonable guess. Admire your persistance and tolerating my ideer of rules, jan.

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    6. Do I get extra credit for identifying the address as Tregay St?

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    7. You do, especially since I didn't know the street we wandered down had a name. Everyone is either on Main St or just off Main Street toward the 730 Mine Trail or on the other side of Clear Creek.

      You get a bonus 1000 miles for next week.

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    8. Population 169, btw. And many of the houses were built right on the creek so effluent could go right into the creek. (ew) It is causing problems now with really high runoff this year and flooded basements...

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    9. Particularly tricky, since it's one of the few streets in town that's not on StreetView. But you can catch a glimpse of a corner from Main St.

      My wife is with her sister's family in Copenhagen. I'm amusing myself by finding their picture locations on StreetView.

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    10. Given the runoff that Colorado mining has produced, I wouldn't get too excited about the effluent of 169 people.

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    11. Well, there now is a sewer system, running water and everything. ;-) But, good point about the mining runoff.

      Streetview is fun. Here's one of my favorite buildings in town. The inside is filled with mining, old west, stuff every square inch. Can you find the address?

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    12. 888 Main St. Plume, Ltd.

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    13. What took you so long? ;-) Great investigating. It's a private residence now ...Plume Ltd might be Gary's business, I imagine.



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  15. On another topic, on April 5, I mentioned the Ebola outbreak in west Africa. At that time, there had been 151 infections, 99 deaths.

    Now, 3 months later, they're up to 779 cases, 481 deaths, for a mortality rate of 62%. Scary stuff.

    We've spoken of board games here. I can recommend a cooperative game on this topic, Pandemic. Very engaging. If you play, you want my daughter-in-law on your team; she has no biomed background, but has a mind like a steel trap.

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  16. Wow, that is very scary! 62 % mortality rate is horrible.

    I have had Pandemic recommended by another friend. My daughter would be good at that too, same quality as your daughter-in-law with the biochem training (and a 20-year-old brain).

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  17. I wonder if your DC-7 kindergarteners could use some anatomy and physiology music videos?

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  18. Hmmmmm. Could be just a tad too advanced for them. I enjoyed them though. This summer, I am teaching 10 year old boys (and one girl). She has told me her secret to surviving being with 15 boys.

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