#Ammonoidea | Explore Tumblr Posts and Blogs

confusedhadrosaur · 4 months

Text

A young Duriavenator hesperis found the empty shell of a Garantiana sp. at the beach (Bajocian, 168 Ma, England).

62 notes · View notes

extinctworld-ua · 1 year

Text

Nipponites

Nipponites — вимерлий рід гетероморфних амонітів. Черепашки ніппонітів (переважно N. mirabilis) сформовані вигинами U-подібної форми, що призводить до появи одних з найхимерніших панцирів, які можна побачити серед амонітів.

Повний текст на сайті "Вимерлий світ":

https://extinctworld.in.ua/nipponites/

18 notes · View notes

i41kazsdj · 1 year

Text

Sensual girl stretches spread crack and loses virginity HOT ASIAN GIRL WITH BIG TITS AND PERFECT BODY sexy newbie honey fucked amateur pov by hairy paki Teaser pinoy Kira Noir whips out her bright purple strapon to seduced Angela White Petite norwegian amateur Filly Stepdaughter get stuffed long in cooter strong after giving wet head Ashley Aoki POV Sucking and Doggystyle Fucking- Short Scene from Snapchat Peta Jensen with girl in cat suit are licking their holes Sub Wife Fingering Her Wet Pussy Asia girl tease high heel

0 notes

safronoviv · 2 years

Text

Ammonitoceras sp

Anthropological Museum, Moscow, 2007. Canon PowerShot S3 IS, f/2.7, 1/50, ISO 200

#ammonoidea #automotivetire #invertebrate #macrophotography #symmetry #terrestrialanimal #automotive #terrestrial #macro photography

1 note · View note

simdertalia · 2 months

Text

🔍🦎 ACNH Museum Fossils Set 4 🦖🔍

Sims 4, base game compatible. 26 items

I hope you enjoy!

Always suggested: bb.objects ON, it makes placing items much easier. For further placement tweaking, check out the TOOL mod.

Build: Floor: Rubber | 6 swatches | Linoleum & Misc

📁 Download all or pick & choose (SFS, No Ads): https://simfileshare.net/folder/212575/

📁 Alt Mega Download (still no ads): https://mega.nz/folder/4hxFkQga#7L92mwjA25qUP_Qi7pMH5g

📁 Download On Patreon

Will be public on March 9th, 2024 💗

Happy Simming! ✨ Some of my sets will be early access from now on. If you like my work, please consider supporting me:

★ Patreon 🎉 ❤️ |★ Ko-Fi ☕️ ❤️ ★ Instagram📷

Thank you for reblogging ❤️ ❤️ ❤️

@sssvitlanz @maxismatchccworld @mmoutfitters @coffee-cc-finds @itsjessicaccfinds @gamommypeach @stargazer-sims-finds @khelga68 @suricringe @vaporwavesims @mystictrance15 @moonglitchccfinds @xlost-in-wonderlandx @jbthedisabledvet @public-ccfinds

-Museum Fossils Set 1 (public from day of post) -Museum Fossils Set 2 (public from day of post) -Museum Fossils Set 3 (public at midnight tonight) -Pamphlet Holder from Reiki Set ☄️Don’t forget the meteor impact display!

The rest of my CC

#s4cc #ts4cc #sims 4 museum #sims 4 dinosaur #sims 4 display #sims 4 pedestal #sims 4 statue #sims 4 fossil #sims 4 maxis match #sims 4 fossils #sims 4 crystals and minerals #sims 4 historical #sims 4 object

161 notes · View notes

bancaishi · 4 months

Text

opening up commissions until the end of december. inquiries can be made through my google form, discord (ammonoideas), email ([email protected]), or DMs.

terms of service & price transcriptions beneath the cut

if you have any questions about any of the following, my tumblr asks & dms are open!

will draw:

original characters

fan art (see information section below)

furries/anthro

simple machinery/robots

moderate gore

suggestive content / nudity

won't draw:

complex machinery / mecha

extreme gore

outright nsfw content

information:

in regards to fan art, i prefer to only take commissions for media i am familiar with, and i may refuse commissions for media that i don't know particularly well or with which i am uncomfortable. if you're unsure about the media you're looking to commission fan art of, you can inquire via tumblr asks or dms.

i will not take commissions in a different art style from my own. this includes commissions where i would be asked to replicate the style of another artist.

overall, i reserve the right to refuse any commission whose contents i am uncomfortable with.

procedure:

after contacting me via google forms, discord, email, or dms, i will respond to accept, confirm, and provide a price for the commission.

payment will be done upfront via paypal invoice (accepts credit/debit cards, paypal, and venmo). i will send confirmation once the payment has been received.

i will send the rough sketch once it's complete and provide additional details such as a rough color palette if needed or requested.

refunds are only possible before the sketch has been completed.

during the process of completing the commission, i will provide work-in-progress images of the artwork at the line art stage, as well as the flat color and fully shaded stages if applicable to check if there are any changes you want to make to the piece at those points.

additional work-in-progress images will be provided alongside any requested alterations made to the artwork. if you would like progress images at any other point in the process, please let me know.

please provide reference images for the subject of your commission. these can include references for the kind of pose, prop, clothing, etc. you would like, but at least one reference for a character or individual being drawn is necessary.

these can be as simple or as complex as you can provide, as long as they are clear. i will not design a character from a written description of them.

you may, however, supplement reference images with written descriptions if there are certain details for which you do not have images.

terms:

the final product of the commission is a digital artwork, and is provided in the form of a PNG or JPG/JPEG file. no physical/material copy is provided.

the artist retains copyright over the finished artwork, as well as any work-in-progress images provided to the commissioner.

the rights to all characters or individuals featured in a commission are retained by their respective owners.

the commissioner may upload or share the final commission artwork on any social media platform, and credit is appreciate but not required. (if you do wish to credit me, i can be found at @bancaishi on instagram and tumblr.)

commissions are for private, non-commercial purposes only. the commissioner may not make use of a commission from me to make a profit, be it through selling/redistributing digitally or physically (as prints, merchandise, etc.). this also applies to NFTs.

commissions may not be used for the purpose or in the process of creating AI/machine-generated images.

the commissioner may not alter the commission without the artist's permission.

prices:

style 1

bust/icon - lined: $10, colored $20

waist up - lined: $20, colored: $30

full body - lined: $30, colored $40

style 2

bust/icon - lined: $15, colored: $30

waist up - lined: $30, colored: $45

full body - lined: $45, colored: $60

additional/complex characters

additional characters: 75% price

additional fees may apply for more complex designs, such as characters with armor, wings, extra limbs, etc.

props & weapons

no additional charge for small or simple props (e.g. an apple, a ball of yarn, a small pencil) unless in high quantity

complex props (style 1): additional $5+

complex props (style 2): additional $8+

animals & monsters

tiny animals (up to the size of a human hand): 20% on their own, free as a companion

small animals (up to the size of a cat): 30%

medium animals (up to the size of a dog): 50%

large animals (human size or larger): 100%

backgrounds

simple background: no additional cost

complex background (style 1): $20+

complex background (style 2): $30+

detailed background (style 1): $80+

detailed background (style 2): $100+

illustrated frames & borders

style 1: $10+

style 2: $15+

rendered scenes

only one slot available

painted scenes starting from $120. price may increase to reflect added detail on characters or backgrounds or an additional illustrated border

#commissions #art commissions #digital commissions #commissions open #character commissions #undescribed

48 notes · View notes

ask-annamary · 5 months

Note

Do you know any ancient sea creatures that you really like, like any specific trilobites or dickinsonia or the famous animalocaris

This world has lived for billions of years, and through out the ages the ocean was filled to the brim with a whole plethora of sea creatures. To the Cambrian Explosion to the age of the dinosaurs, countless species “rules” the oceans. Forgive my sketches here, they could never encapsulate the true glory and scale of these creatures.

One creature that may seem familiar is the Macroscaphite, belonging to the extinct subclass of Cephalopods named Ammonoidea. You may know them better as the common name of “ammonite”. One may be familiar with the modern day Nautilus and assume that it is a long lasting member of this subclass due to their striking similarities, but ammonite were actually closer related to the subclass Coleoidea. This is the group of shell-less cephalopods such as octopi and squid.

Back in the day many ammonites had rather absurd shells, not just the polite little spiral you may sea in many textbooks. Some where cones spiraling up in the most ridiculous manner, some possessed dangerous ridges and spikes, others… well, as you can see with Macroscaphite… I cannot even begin to describe what this shape reminds me of. It is somewhere between a trombone, a paper clip, and a slide whistle. It is as if they all came together and had an abyssal child together, how beautiful.

Sacabambaspis is a mouthful of a name, which is funny to conchsider when you remember that it is a jawless genus of fish. “But Mary,” you say, “how can this fish eat without a jaw?” For this you can look to living examples such as lampreys and hagfish. These specimen can latch onto larger animals like a suction cup. Adult lampreys are parasitic in nature, scraping a “tongue” against their host for a good mouthful of meat. This does not kill the host, that would be bad for the parasite, but it is rather uncomfortable to say the least. I’m saying this from experience. Not enough is known about Sacabambaspis as a whole to say if it was a parasite itself. It is likely that it employed a similar sucking motion to collect food.

As for the Archelon… What a magnificent creature it is, no? The largest documented turtle to swim the seas. Approximately 15ft from head to tail, this reptile would’ve been taller than I am! Can you imagine that? Someone larger than me? There are the boss cogs, yes, but outside of that bunch there aren’t many who rival me in size. Much like the living leatherback sea turtle, Archelon would’ve had a leathery shell, or carapace, unlike other hard shelled turtles. Who knows what prehistoric jellyfish or squid this beast may have consumed. It is hard to imagine such a large fortress of an animal to be contested in its oceans, but during its life the Archelon would’ve shared its waters with large marine reptiles such as the mosasaur.

[The Deep Diver sighs, shutting her notebook and tucking it into a comically small pocket on her suit.]

If only I could have the chance to meet these creatures, even if it is only for a moment… oh well. No reason to dwell in the past, to have suck silly dreams swimming around in my helmet.

#deep diver #toontown #toonblr #toontown corporate clash #prob art #ttcc #fish facts blast GO

34 notes · View notes

pwlanier · 9 months

Text

HETEROMORPH AMMONITE

Ephamulina arcuata

Cretaceous, 100 million years

Madagascar

29 × 24 × 10 cm

Ammonites (Ammonoidea) are a distinct group of molluscs, the fossilised shells of extinct cephalopods. They were sea creatures whose shells were spiral-shaped. The uncoiled shell of this heteromorph ammonite indicates that it was a poor swimmer, drifting in the plankton, collecting small animals on long tentacles like modern jellyfish or moving slowly like a clam. Ammonites died out at the end of the Creataceous period, 65 million years ago, together with the dinosaurs. Thanks to the variety of their forms they remain a very popular collectors’ item.

This is a very nice example of a heteromorph ammonite – fossilized through pressure, heat, depth and time, consisting of calcite, pyrite and silicic acid. Its colouration varies between flesh-coloured, pinkish and sand-coloured nuances.

Koller

23 notes · View notes

sparkiekong · 7 months

Text

There's this scientist who releases tests on 'alien' fossils, says they're 30 % not of this world...while failing to mention that 70% is from this world.

That's not alien man... that's an unidentified species. Octopus, Squid, Cuttlefish, Nautiloids, and Ammonoidea all fall around that percentage range I think. We don't call those guys alien.

Also he fails to mention that he's been debunked a few times for crying alien when it wasn't. It was just weird shit humans do to their kids.

Not denying the universe is too big for their not to be life in other places, but I am more inclined to believe that we're not important enough for an advanced species to drop by and say hello unless they're trapped on this flying rock with us.

Occam's Razor, simplest answer is likely true. Species who exist here have a stake in what happens here telling us idiots to stop wrecking up home... or mega-advanced light year traveling space aliens come down to "test" and kill cows and float around in the sky so people can take blurry ass videos with their 3000 dollar phones...

I mean burgers are delicious... but what's the point?

#kong rambles #nonsims #people suck

12 notes · View notes

infonotes-ru · 1 year

Text

Аммониты, загадка божественного названия

Аммониты - разговорное название представителей Ammonoidea, подкласса древних головоногих с раковинами, напоминающими закрученный рог барана. Которые впервые появились в девонский период (419,2 млн лет назад - 358,9 млн лет назад) и процветали в земных океанах. Пока мел-палеогеновое вымирание не уничтожило их около 66 миллионов лет назад. Поскольку аммониты были чрезвычайно широко распространены в океанах на протяжении более трехсот миллионов лет, их окаменелые раковины чрезвычайно распространены во многих районах по всему миру. Десятки миллионов лет спустя, в гораздо более позднем прошлом, древние египтяне и кушиты поклонялись богу Амону. Которого они изображали либо с головой, либо иногда просто с бараньими рогами. Позже греки и римляне стали поклоняться этому богу, называя его Аммоном. И отождествляя со своим богом Зевсом/Юпитером. Они идентифицировали окаменелые раковины аммонитов как напоминающие рога Аммона. И, следовательно, полагали, что они были своего рода священным камнем, способным вызывать пророческие сны. Именно от имени Аммон аммониты получили свои современные общеупотребительные и научные названия.

Египетский бог Амон

Древние египтяне поклонялись богу Амону, который становился все более влиятельным в ходе египетской истории. Он впервые засвидетельствован в Древнем Царстве (2686 - 2181 г. до н.э.). Амон приобрел большее значение в течение Первого промежуточного периода (2181 - 2055 г. до н.э.). Во времена Одиннадцатой династии (2150 - 1991 г. до н.э.) он вытеснил бога Монту в качестве божественного покровителя города Васет. Который широко известен под греческим названием Фивы. С царями Фив в качестве правителей Египта Амон, бог-покровитель Фив, поднялся до самого высокого, самого возвышенного статуса в египетском пантеоне. Египтяне связывали его с богом солнца Ра, как Амон-Ра. И стали считать его верховным богом-творцом. С того времени и далее, египетские фараоны способствовали отождествлению главного бога с головой барана с Амоном-Ра. И заказали множество художественных изображений Амона-Ра с головой (или иногда просто рога) барана.

Растущие контакты между греками и египтянами

Засвидетельствовано, что греки были в контакте с египтянами с самых ранних письменных источников. Примерно с седьмого века до н.э. контакты между греками и египтянами значительно увеличились. Присутствие греческих торговцев и купцов в Египте, похоже, также увеличилось. Есть даже свидетельства того, что некоторые греки из высшего сословия начали посещать Египет. Как то, что мы могли бы назвать туристами. Чтобы увидеть впечатляющие египетские города, храмы и памятники. Примерно в это же время греческие поселенцы также начали основывать постоянные колонии недалеко от Египта. И, в конечном итоге, в самом Египте.

Культ Аммона в греческом мире

Контакт с египетской культурой и религией познакомил греков с богом Амоном. Греки, особенно те, кто жил в районе Киренаики на территории современной Ливии, начали поклоняться ему под именем Ἄμμων (Аммон). И отождествляли его с Зевсом, главным богом их собственного пантеона. К концу пятого века до нашей эры культ Аммона распространился по большей части греческого мира. Изображение Аммона с полной бараньей головой, по-видимому, не очень нравилось грекам. Возможно, потому, что они привыкли поклоняться антропоморфным божествам. Так, греки обычно изображали Аммона в своем искусстве, используя стандартную иконографию Зевса. Только с парой бараньих рогов, прикрепленных по бокам его головы. Именно от этого египетские изображения Зевса имеют баранью голову. Отсюда и аммонийцы получили свое название, ибо египтяне называли Зевса Амоном. Поклонение Аммону стало более распространенным среди греков в эллинистическую эпоху. Между тем, по мере того как римское государство расширялось за счет завоевания и аннексии новых территорий, римляне подверглись воздействию культа Аммона через греков. Таким образом, римляне стали поклоняться и Аммону, отождествляя его с Юпитером. Главным богом их собственного пантеона, которого они также отождествляли с Зевсом.

Как аммониты получили свое современное название

Когда древние греки и римляне столкнулись с окаменелыми аммонитами, они интерпретировали их как тип священного камня с особыми способностями. Потому что они напоминали рога Аммона. Древнеримский писатель Плиний Старший (жил ок. 23–79 гг. н. э.) упоминает окаменелости аммонита в своем труде "Естественная история". Он называет их именем Hammonis cornua, что означает "рога Аммона". И описывает их как священный камень, найденный в Эфиопии. Который, как говорят, вызывает у людей пророческие сны. "Естественная история" Плиния стала, возможно, самым влиятельным текстом по ранней современной геологии, ботанике, зоологии и таксономии. Следовательно, в эпоху Возрождения ученые использовали название, данное Плинием для описания окаменелых аммонитов. Позже натуралисты поняли, что то, что Плиний понимал под горными породами, уже было окаменевшими остатками первобытного подкласса головоногих. Немецкий натуралист Иоганн Филипп Брейне применил латинское название Ammonites к этому подклассу. Французский таксономист Жан Гийом Брюгьер (1749–1798 гг.) популяризировал это название. А в 1884 немецкий палеонтолог Карл Альфред фон Циттель ввел научное название Ammonoidea для подкласса, к которому принадлежат аммониты. Read the full article

#аммониты #древняяГреция #Египет #история #наука

0 notes

buckskilop · 2 years

Text

Mos def the ecstatic full album

#MOS DEF THE ECSTATIC FULL ALBUM MOVIE#

#MOS DEF THE ECSTATIC FULL ALBUM FULL#

#MOS DEF THE ECSTATIC FULL ALBUM CODE#

#MOS DEF THE ECSTATIC FULL ALBUM ZIP#

#MOS DEF THE ECSTATIC FULL ALBUM DOWNLOAD#

Bulletins of American Paleontology 363: 1–560. A compendium of fossil marine animal genera. Geological Society of America and University of Kansas Press Mesozoic Ammonoidea, Treatise on Invertebrate Paleontology, Part L. This genus is derived from Necraticeras, and is characterized by having a long, slightly curved body, an umbilical breccia or acerosella, and a smooth venter.Īrkell et al., 1957. Rebecoceras is a genus of ammonites from the Early Cretaceous from Mongolia.

#MOS DEF THE ECSTATIC FULL ALBUM FULL#

Mos Def, The Ecstatic full album zip.Rebecoceras Mos Def, The Ecstatic (2009) full album zip.

#MOS DEF THE ECSTATIC FULL ALBUM DOWNLOAD#

Mos Def, The Ecstatic (2009) (MP3 Download Album) Get the full album by Mos Def. The album will still be released next week. Mos Def, Peaceful (2009) (MP3 Download Album) Get the full album by Mos Def. After early reports of Mos Defs The Ecstatic being pushed back spread online, a rep for the rapper has called the claims false. Browse similar in: Neo-Soul albums Hip Hop albums Conscious Hip Hop albums East Coast Hip Hop albums. Your site is doing this great! Would you like to redirect it for me? If yes let me know and I'll surely send you a link! Congrats 8, 1999 The Ecstatic Studio Album by Mos Def released in 2009. The download links of 'Mos Def, The Ecstatic' on this page are tested daily by my team, fans and visitors and always working.

#MOS DEF THE ECSTATIC FULL ALBUM ZIP#

Mp3 Music freeload the full album Mos Def, The Ecstatic zip download. Mos Def - Black On Both Sides (1999) (MP3 Download Album) Get the full album by Mos Def. …To me the job of an artist is to provide a useful and intelligent vocabulary for the world to be able to articulate feelings they experience every day.Mos Def, The Ecstatic full album zip. It’s machine-like how things are run in hip-hop now, and my ambitions are different. “You have to experience life, make observations, ask questions. In a recent conversation with Spank Rock for Interview magazine, Mos Def elucidated: Still, given an acting schedule the past three years that has included roles in The Hitchhiker’s Guide to the Galaxy, 16 Blocks, Be Kind Rewind and Cadillac Records, it’s remarkable how razor-sharp The Ecstatic is - and how committed he remains to the musical side of his artistry. Tracks such as “Life in Marvelous Times” reveal the big vision you’d expect from a talent who has earned Grammy, Emmy and Golden Globe nominations, as well as acted in Suzan Lori Parks’ Pulitzer Prize-winning play Topdog/Underdog on Broadway. His dulcet flow and brisk storytelling hold it all together, as, joined by guests such as Slick Rick and Talib Kweli, his rhymes take the listener to the perilous inner city and even-more-treacherous distant lands, railing against the frailties and oppression that make them parallel worlds. Flash - is a Middle Eastern sampler platter served up with an island music cocktail and a side order of electro. ecstatic, ecstatic meaning, ecstatic synonym, ecstatic dance, ecstatically, ecstatic meaning in urdu, ecstatic. The Ecstatic’s production - from the likes of Madlib, Oh No, Georgia Anne Muldrow and Mr. Fix Mos Def, The Ecstatic Full Album Zip. The New Danger Black on Both Sides Other Rap albums: Das Efx - Generation. The man born Dante Terrell Smith has hit pay dirt by being bold musically and almost sage lyrically. A Mos Def album, with duration of: 45:38. Gabriel Boylan of Spin: “The former Black Star co-captain is among our greatest MCs, and ‘The Ecstatic’ is easily his finest full-length since ‘Black on Both Sides,’ his 1999 solo debut.” And from Sach O on Passion of the Weiss: “Mos Def has finally dropped the album you’ve been waiting for after a decade lost in the wilderness.” Writes Nate Patrin on Pitchfork: “This is Mos Def’s small-globe statement, an album that comfortably jumps stylistically across continents on a hip-hop goodwill-ambassador tour… an album that most people will hear first and foremost as the comeback bid of a rapper-turned-actor, but also an important indication that Mos… has a stake in something greater than just one corner of the rap world…”Īdds J. To hear some of the feedback, you’d think critics would have given the shirts off their back for the new project. Gimmick or innovation? It doesn’t matter - The Ecstatic, released in June on Downtown Records, is proving a style statement unto itself, earning the 35-year-old Brooklyn native some of the best reviews of a career that blossomed with his work in the late 1990s with Rawkus Records crew.

#MOS DEF THE ECSTATIC FULL ALBUM MOVIE#

It might be a funny scene, movie quote, animation, meme or a mashup of multiple sources.

#MOS DEF THE ECSTATIC FULL ALBUM CODE#

Yes, it’s true: Clothing line LnA recently unveiled the Mos Def Music Tee, a shirt with album art, tracklist and a tag imprinted with a URL and download code for his fourth solo album, The Ecstatic. You can take any video, trim the best part, combine with other videos, add soundtrack. Perhaps the only development more surprising than Mos Def’s re-ascension to the hip-hop summit - some 10 years after Black Star, his collaboration with Talib Kweli, foreshadowed icon status - is the fact that he’s one of the first artists ever to have an album released as a T-shirt.

#Mos def the ecstatic full album

0 notes

extinctworld-ua · 10 months

Text

Sphenodiscus

Sphenodiscus плаває поряд з Pharmacicnthys у пізньому крейдяному морі.

Sphenodiscus — вимерлий рід акантоцератоподібних амонітів. Рід був знайдений на багатьох континентах і, як вважають, був широко розповсюдженим під час маастрихтського етапу пізньої крейди. Це був один з останніх амоноїдів, що еволюціонував до зникнення всього підкласу в палеоцені, котре сталося одразу після крейдово-палеогенового вимирання.

Повний текст на сайті "Вимерлий світ":

https://extinctworld.in.ua/sphenodiscus/

4 notes · View notes

nyc-uws · 2 years

Text

Dinosaurs of the beginning of the Jurassic period

youtube

The Jurassic period, or the Jura, is probably the most interesting era. After watching the famous movie “The Jurrasic Park”, an average person might think that the Earth was populated only by dinosaurs, like T-rex. In fact, it wasn't quite like that even though the Jurassic period is also known as the Age of Reptiles. Let's start with the statement that the Jurassic period, the second in the Mesozoic era, is long and complex. It began 201 million years ago and lasted about 56 million years. It got its name because the fossils were first discovered and explored in the Jura mountains in Switzerland and France. Hence the name of the period. This era is divided into three stages. The first, which lasted from 201.3 to 174.1 million years ago, is called the Lower Jurassic. At that time, life was recovering from the Triassic-Jurassic extinction that caused about half of all animal species on the planet to disappear. However, the hot and humid climate of the Jura helped life to quickly bounce back. Warm oceans and seas abounded with Ammonoidea, Belemnitida, fish and reptiles. On land, reptiles including dinosaurs quickly filled the ecological niches freed by the previous extinction. In the process of evolution, some reptiles got wings and flew into the sky. The beginning of the Jurassic period launched the high time for reptiles. Hundreds of dinosaur species appeared on the planet. They settled on all continents, including Antarctica. Some reached incredible sizes and proportions. Some, of course, developed formidable shapes, sometimes bizarre and scary. What are the mysteries of the prehistoric reptiles that lived on Earth 200 million years ago? Dinosaurs of the beginning of the Jurassic period.

#Dinosaurs #Youtube

0 notes

coutellerielefidele · 2 years

Photo

Ah Monique ... Non pas du tout, on recommence !! Les ammonites au sens large, ou Ammonoidea, sont une sous-classe éteinte des mollusques céphalopodes. Elles apparaissent dans le registre fossile durant le Dévonien et disparaissent peu après la crise Crétacé-Paléogène. #ammonite #fossil #couteau #Coutellerie #fossilwatch #knifefanatic #knifenews #lefidele @coutellerielefidele (à Auvergne, France) https://www.instagram.com/p/CivenyorF8y/?igshid=NGJjMDIxMWI=

#ammonite #fossil #couteau #coutellerie #fossilwatch #knifefanatic #knifenews #lefidele

0 notes

sorarium · 2 years

Photo

アンモナイト（分類名：アンモナイト亜綱、学名：subclassis Ammonoidea）本物のアンモナイトの化石を樹脂に閉じ込めたヘアゴムです。渦の中央に小さなSWAROVSKIを配し、アンモナイトを模したチャームを添えました。

アンモナイトのヘアゴム https://minne.com/items/8090858 https://www.creema.jp/item/13770133/detail https://minne.com/@sorarium-min https://www.creema.jp/c/sorarium/item/onsale

#minneで販売中 #creemaで販売中 #sorarium

0 notes

alphynix · 2 years

Photo

Retro vs Modern #17: Ammonites

Ammonites (or ammonoids) are highly distinctive and instantly recognizable fossils that have been found all around the world for thousands of years, and have been associated with a wide range of folkloric and mythologic interpretations – including snakestones, buffalo stones, shaligrams, and the horns of Ammon, with the latter eventually inspiring the scientific name for this group of ancient molluscs.

(Unlike the other entries in this series the reconstructions shown here are somewhat generalized ammonites. They're not intended to depict a specific species, but the shell shape is mostly based on Asteroceras obtusum.)

1830s

It was only in the 1700s that ammonites began to be recognized as the remains of cephalopod shells, but the lack of soft part impressions made the rest of their anatomy a mystery. The very first known life reconstruction was part of the Duria Antiquior scene painted in 1830, but to modern eyes it probably isn't immediately obvious as even being an ammonite, depicted as a strange little boat-like thing to the right of the battling ichthyosaur and plesiosaur.

The argonaut octopus, or "paper nautilus", was considered to be the closest living model for ammonites at the time due to superficial similarities in its "shell" shape, but these modern animals were also rather poorly understood. They were commonly inaccurately illustrated as floating around on the ocean surface using the expanded surfaces on two of their tentacles as "sails" – and so ammonites were initially reconstructed in the same way.

1860s

While increasing scientific knowledge of the chambered nautilus led to it being proposed as a better model for ammonites in the mid-1830s, the argonaut-style depictions continued for several decades.

Interestingly the earliest known non-argonaut reconstruction of an ammonite, in the first edition of La Terre Avant Le Déluge in 1863, actually showed a very squid-like animal inside an ammonite shell, with eight arms and two longer tentacles. But this was quickly "corrected" in later editions to a much more nautilus-like version with numerous cirri-like tentacles and a large hood.

The nautilus model for ammonites eventually became the standard by the end of the 19th century, although they continued to be reconstructed as surface-floaters. Bottom-dwelling ammonite interpretations were also popular for a while in the early 20th century, being shown as creeping animals with nautilus-like anatomy and numerous octopus-like tentacles, before open water active swimmers eventually became the standard representation.

2020s

During the 20th century opinions on the closest living relatives of ammonites began to shift away from nautiluses and towards the coleoids (squid, cuttlefish, and octopuses). The consensus by the 1990s was that both ammonites and coleoids had a common ancestry within the bactridids, and ammonites were considered to have likely had ten arms (at least ancestrally) and were probably much more squid-like after all.

Little was still actually known about these cephalopods' soft parts, but some internal anatomy had at least been figured out by the early 21st century. Enigmatic fossils known as aptychi had been found preserved in position within ammonite shell cavities, and were initially thought to be an operculum closing off the shell against predators – but are currently considered to instead be part of the jaw apparatus along with a radula.

Tentative ink sac traces were also found in some specimens (although these are now disputed), and what were thought to be poorly-preserved digestive organs, but the actual external life appearance of ammonites was still basically unknown. By the mid-2010s the best guess reconstructions were based on muscle attachment sites that suggested the presence of a large squid-like siphon.

Possible evidence of banded color patterns were also sometimes found preserved on shells, while others showed iridescent patterns that might have been visible on the surface in life.

In the late 2010s the continued scarcity of ammonite soft tissue was potentially explained as being the same reason true squid fossils are so incredibly rare – their biochemistry may have simply been incompatible with the vast majority of preservation conditions.

But then something amazing happened.

In early 2021 a "naked" ammonite missing its shell was described, preserving most of the body in exceptional detail – although frustratingly the arms were missing, giving no clarification to their possible number or arrangement. But then just a few months later another study focusing on mysterious hook-like structures in some ammonite fossils concluded that they came from the clubbed tips of a pair of long squid-like tentacles – the first direct evidence of any ammonite appendages!

A third soft-tissue study at the end of the year added in some further confirmation that ammonites were much more coleoid-like than nautilus-like, with more evidence of a squid-style siphon, along with evidece of powerful muscles that retracted the ammonite's body deep inside its shell cavity for protection.

Since ammonites existed for over 340 million years in a wide range of habitats and ecological roles, and came in a massive variety of shapes and sizes, it's extremely likely that their soft anatomy was just as diverse as their shells – so there's no single "one reconstruction fits all" for their life appearances. Still, at least we now have something less speculative to work with for restorations, even if it's a bit generalized and composite, and now that we're finally starting to find that elusive soft tissue there's the potential for us to discover so much more about these iconic fossil animals.

———

Nix Illustration | Tumblr | Twitter | Patreon

#retro vs modern 2022 #science illustration #paleontology #paleoart #palaeoblr #ammonite #ammonoidea #cephalopod #mollusc #invertebrate #art #you wait centuries for ammonite soft tissue #and then a bunch turns up all at once

3K notes · View notes