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cab67

(3,789 posts)

10. Chances are...

Reply to Martin68 (Reply #7)

Sat Apr 11, 2026, 04:42 PM

Saturday

...the species you dissected was Squalus acanthias. They actually have bony dorsal fin spines.

They don't have internal bone, which is why you could whittle the braincase with a scalpel. BUT - unlike most extinct shark groups, the living shark radiations (Neoselachii) have calcified cartilage in their vertebral column. The vertebral centra aren't bony, but they develop calcium carbonate deposits. (Bone is calcium phosphate.). This gives them more rigidity.

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useless natural history trivia V [View all] cab67 Saturday OP

Fascinating! TY for sharing! SheltieLover Saturday #1

An example is flamingos are pink because of their diet. Hugin Saturday #2

;-{}..... Goonch Saturday #3

THat's a Jackalope if I've ever seen one Jerry2144 Saturday #5

And I thought it was a horny Easter Bunny. erronis Saturday #6

another fun fact - cab67 Saturday #11

Did you take the picture of the Smithsonian mount? cab67 Saturday #13

Ceratogaulus hatcheri skeleton, Museum of Natural History, Washington D.C. Goonch Saturday #14

I have found several blue jay feathers. efhmc Saturday #4

As the OP mentioned, blue jay feathers have no blue pigment. They are blue because of the way they diffract light. Martin68 Saturday #8

Wet the feather, Tom Dyer Saturday #9

The light hits the feather the same way whether it's attached to the bird or not. cab67 Saturday #12

When I dissected a shark in comparative Anatomy class I was able to carve away the skull from around the Martin68 Saturday #7

Chances are... cab67 Saturday #10

All Perceived Colors Result From How "Light Bounces Off Them." ColoringFool Saturday #15

yes, but... cab67 Saturday #16