SEA BISCUITS: THEY REALLY DO CONTAIN DOVES – AND MORE!


Sea Biscuit Close-up, Abaco (Keith Salvesen)

SEA BISCUITS: THEY REALLY DO CONTAIN DOVES – AND MORE!

Recently I posed the question whether sea biscuits, like sand dollars contain ‘doves’. I had one in my hand, it rattled, I took a photograph through its ‘mouth hole’ and the question was answered. Biscuits do indeed contain doves – see HERE for details and comparisons with dollar doves.

Sea Biscuit 'Doves', Abaco (Keith Salvesen)

However, I spinelessly* failed to break open the biscuit to check out the contents more closely. I theorised that, because of the 5-way symmetry of these creatures, there would be 5 doves (which are in fact segmented mouth parts) in a biscuit exactly as with a dollar, and amiably challenged anyone to disprove it. [* biscuits and dollars are types of sea urchin – see what I did there?]

Dollar dove in close-up – one of 5 segmented mouth parts inside the ‘test’ (skeleton)Sand Dollar 'Doves', Abaco (Keith Salvesen)

Melissa Ann Guinness from Hope Town has a far more robust attitude to these things and, taking up the challenge, she heartlessly smashed open a sea biscuit from her collection to investigate further. I said I’d publish a correction if my theory was wrong. This is it – though in one arguable sense the theory holds good. It just didn’t go far enough…

Sea Biscuit 'Doves', Abaco (Melissa Ann Guinness)

In the above picture you can see (a) 4 quarters of a sea biscuit skeleton (b) 10 demi-doves (rather than 5 whole doves) and (c) a small mummified 5-limbed brittle star that was presumably in the creature’s digestive system when it died.

10 ‘demi-doves’  (or, when assembled, 5 doves that (unlike sand dollars) are in 2 parts
Sea Biscuit 'Doves', Abaco (Melissa Ann Guinness)

Complete doves

Sea Biscuit 'Doves', Abaco (Melissa Ann Guinness) Sea Biscuit 'Doves', Abaco (Melissa Ann Guinness) Sea Biscuit 'Doves', Abaco (Melissa Ann Guinness)

The final reconstruction – 5 doves and a bonus brittle star

Sea Biscuit 'Doves', Abaco (Keith Salvesen)

Photo Credits: Keith Salvesen (1, 2, 3, 10); Melissa Ann Guinness (4, 5, 6, ,7 ,8 ,9)

SEA BISCUITS: DO THEY REALLY CONTAIN DOVES?


Sea Biscuits, Delphi, Abaco (Clare Latimer)

Sea Biscuits on the Beach, Delphi, Abaco Bahamas

SEA BISCUITS: DO THEY REALLY CONTAIN DOVES?

A couple of years ago I wrote a post called ECHINODERMS, DOLLAR DOVES & PETRIFIED BISCUITS. It dealt with the… fact? rumour? old wive’s tale?… that within each sand dollar test (i.e. the white skeleton) are hidden 5 ‘doves’. You can hear them rattling inside if you shake the dollar… 

Sand Dollar Doves (Keith Salvesen) 6

Sand Dollar from Abaco containing 5 miniature white doves…

I investigated the theory with senior granddaughter, and we broke a sand dollar in half. And as you can see, the answer was undoubtedly yes – there were 5 tiny white doves, thus fulfilling the prediction of the famous ‘Sand Dollar’ poem that contains the lines  “Now break the centre open And here you will release The five white doves awaiting To spread good will and peace”.

Five white doves (in fact, the separated parts of the creature’s feeding apparatus)Sand Dollar Doves (Keith Salvesen) 1

A single dove, a picture of dovelinessSand Dollar Doves (Keith Salvesen) 3

I never thought to extend the experiment to sea biscuits, another object prized by beachcombers. All that changed last month when I picked up a sea biscuit and found that it, too, rattled.

A rattling good sea biscuit

So I turned it over to take a closer look at the underside. And there, unmistakably, was the source of the rattle – some kind of internal arrangement inside the feeding  hole (let us not pause overlong to consider the purpose of the other hole). But it wasn’t conclusively a dove.

So I shook it around a bit (sorry, doves) and zoomed in. And there was a small white columbine-type contraption remarkably similar to those found in the dollar dove. And no, I did not smash open the sea biscuit (it wasn’t actually mine). And no, I didn’t doubt any longer that sea biscuits also contain doves.

SO WILL THERE BE 5 DOVES, LIKE WITH THE DOLLARS?

I predict there will also be five. Both dollars and biscuits have ‘five-way symmetry’ (look on the topside of a biscuit or dollar to see how); and so the mouth (from which the ‘doves’ derive) will have a single part for each of the five sectors, all linked. 

If anyone would like to smash up one of their precious beach finds and test the theory, please feel free. Prove me wrong… and I’ll publish a correction! [Photo please…]

All photos Keith Salvesen except Header, Clare Latimer at Delphi

ECHINODERMS, DOLLAR DOVES & PETRIFIED BISCUITS


Sand Dollar Doves (Keith Salvesen) 6

Sand Dollar from Abaco containing 5 miniature white doves…

ECHINODERMS, DOLLAR DOVES & PETRIFIED BISCUITS

Echinoderms (Gr. ‘Hedgehog Skin’) comprise a large variety of sea creatures characterised (mostly) by radial symmetry, often five-way. For Abaconians, the most frequently encountered are starfish, sea urchins, sand dollars and sea biscuits. I am going to look at two particular aspects of dollars and biscuits, conscious that my illustrative photos of white objects were stupidly taken against a white background.

DOLLAR DOVES

I’m sure all Bahamians know or are aware of at least one version of the famous ‘Sand Dollar’ poem, in which the various characteristics of the test (the skeleton of the creature) are given religious significance. One verse of the poem may be puzzling: “Now break the centre open And here you will release The five white doves awaiting To spread good will and peace”.

Recently, Senior Granddaughter (10 this week) was looking at some Abaco sand dollars in her unfeasibly huge collection of shells. She picked one up, shook it and it rattled. She said a friend at school had told her that a rattling sand dollar has ‘doves’ inside it, and asked if we could break it open and see. I’ve learnt that it is useless to argue with her – she has the tenacity of a trial lawyer – so we did. This is what we found.

Sand Dollar with a spiky interior like a white cave with stalagmites and stalagtitesSand Dollar Doves (Keith Salvesen) 4

Five white doves (in fact, the separated parts of the creature’s feeding apparatus)Sand Dollar Doves (Keith Salvesen) 1

Two broken pieces showing where the doves are centrally locatedSand Dollar Doves (Keith Salvesen) 5

A single dove (best viewed the other way up for full-on doveliness)Sand Dollar Doves (Keith Salvesen) 3

The photo below, from Pinterest, shows the ‘mouth’ with its 5 dove-parts intact, an arrangement called ‘Aristotle’s Lantern’.

Sand Dollar : Aristotle's Lantern : Doves (Pinterest)

PETRIFIED BISCUITS

In common parlance ‘petrified’ is an extreme version of ‘terrified’. Literally, it means ‘turned to stone’ (L. Petrus, a rock). It is descriptive of a state of fossilisation, where an animal skeleton or dead wood or plant matter turns over aeons into stone. Undaunted by her Doves discovery, SG (a most inquisitive girl) also discovered a box containing random stones and fossils. She found these two items:

Fossilised sea biscuitsPetrified Sea Biscuit (Keith Salvesen) 1

A closer look at the pair of rocksPetrified Sea Biscuit (Keith Salvesen) 5 Petrified Sea Biscuit (Keith Salvesen) 4

The undersides of the fossils above – looking like stones but with some tell-tale small holesPetrified Sea Biscuit (Keith Salvesen) 2 Petrified Sea Biscuit (Keith Salvesen) 3

A close-up of the pale biscuitPetrified Sea Biscuit (Keith Salvesen) 6

Sea biscuits as everyone knows them, on the beach at Delphi – skeletons but not yet fossilsSea Biscuits, Delphi, Abaco (Clare Latimer) copy

A ‘modern’ sea biscuit in close-upSea Biscuit, Abaco (Rhonda Pearce) copy

FUN FACT

Florida has an unofficial but proposed State Fossil, the ‘Sea Biscuit (Eocene Age)’. I didn’t know it before, but it turns out that around 40 States have State Fossils. Whatever next? State Bacteria?

SO HOW OLD MIGHT A PETRIFIED BISCUIT BE?

The fossil biscuits I have looked at, from Florida to Madagascar, are said to come from three specific historic epochs – from the oldest, Jurassic (145m – 201m years ago),  to Eocene (34m – 56m) and Pleistocene (0.01m – 2.6m). 

HOW DOES THAT HELP ANYBODY? BE MORE PRECISE

By all means. Here is an excellent Geochart that gives an idea of the time span. A Jurassic sea biscuit would be more than 145m years old. So maybe the next plan should be to take the 2 petrified sea biscuits plus SG to a museum to see if we can get an idea of their age…geotimescale

All photos ‘in-house’ except the Delphi biscuits, Clare Latimer & the single biscuit Rhonda Pearce; Geochart to be credited asap, mislaid the source…