Episode 160 – Venus’ Flower Basket: A Structure Like Steel

“…and today we’re talking about a coveted animal crossing catch. But not much more on that later.”

The sponge life is a simple one. With nowhere to go and no way to get there, a sponge needs to make the most of its surroundings. To protect against the current, sponges form skeletons out of whatever’s around them. For instance, if you’re surrounded by calcium, you may make a chalk skeleton. But what if all you have around you is sand? Venus’ flower basket finds itself in such a predicament. But making a strong skeleton out of a delicate substance is just it’s lot in Life, Death, and Taxonomy. 

Description of Venus’ Flower Basket

  • These things don’t really look like your typical sea sponges.
  • They’re totally tubular, which isn’t uncommon among sponges. But they have a unique white lattice structure that makes them look like a fancy doily or a medieval horn made out of dryer lint.
  • Their bodies are long and curved
  • Here is how Wikipedia describes the lattice structure: “A syconoid type of canal system is present, where ostia communicate with incurrent canals, which communicates with radial canals through prosopyles (proso-piles) which, in turn, open into spongocoel (sponge-o-ko-el) and outside through osculum (oskullum).”
  • In any case, some speculate that it uses its own bioluminescence to attract plankton to it.

Measure Up

Welcome to the beloved Measure Up segment. The official listener’s favorite part of the show! The part of the show when we present the animal’s size and dimension in relatable terms through a quiz that’s fun for the whole family. It’s also the part of the show that’s introduced by you when you send in audio of yourself saying, singing, or chittering the words measure up into ldtaxonomy at gmail dot com. We don’t have a Measure Up intro this week, which means we get to hear from an animal and Carlos has to guess what it is.

  1. Eurasian Wolf
  2. Plains Wolf
  3. Arabian Wolf
  4. Arctic Wolf

Basket Length

  • 25 cm (10 inches)
  • How many of the Brookesia nana chameleons go into Venus’s Flower basket?
  • Hint: The chameleon was discovered in Madagascar and was first described this year in 2021. It may be the smallest reptile alive. 
  • 18.8 chameleons. The chameleon is just 13.5 mm.

Fiber Length

  • The glassy fibers that attach the basket to the seafloor are as thin as a hair and about 8 inches long. 
  • How many of these fibers go into the length of Dmitriy Donskoy, TK-208.
  • Hint: The sub is a typhoon class russian navy ship and it’s the largest submarine in the world.
  • 861 fibers. The ship is 175 meters (574 feet).

Fast Facts About the Venus’ Flower Basket

  • Range: They live at the bottom of the ocean near the Philippines up to 2500 meters (8,200 ft – over a mile and a half) below the surface.
  • Diet: They eat plankton filtered out of the ocean
  • The glass sponge shrimp often spends its entire life inside the VFB. 
    • A breeding pair will sometimes swim into the sponge when they’re small and feed off the plankton.
    • However, they will grow too large to leave the sponge’s lattice structure and will have to spend their entire lives inside.
    • Their offspring will be small enough to leave and find sponges of their own.
    • The shrimp clean the sponge and the sponge provides food and protection. 
    • The love story of these two trapped shrimp lovers has made the VFB a symbol of undying love in Japan. Dried specimens are often given as wedding gifts.

Major Fact: Unbreakable Glass

The venus flower basket is literally made of glass, or more accurately, silica. Sponges all have structural elements called specials that are the building blocks that form their bodies. These silica spicules form the unique look and shape of the Venus’s flower basket.

A glass tube sounds like it would be extremely delicate, but the sponge needs to withstand ocean currents, detritus, and the occasional bump from sea life. So, the structure of the basket is said to make it as strong as steel. How?

To understand how, researchers have looked very closely at the construction of the tube as a whole and at the spicules themselves. At the most basic level, each glass fiber is actually many layers of glass. Each layer is only micrometers thick, and can be just thicker than the width of a molecule. This is something we can’t ever reproduce with glass yet. 

Layered glass is much stronger and can absorb more force than a single layer of thick glass. That’s why hurricane and bullet proof glass has multiple layers. So the fibers are already extraordinarily intricate and strong. 

Looking at the basket, it seems like it has a wicker pattern, but it’s more like a criss cross of layered apertures. Each spicule is a cross that’s slightly skewed like an italicized X. As these crosses are layered, instead of forming perfect squares windows, they form circular openings. Circles are structurally more durable than squares. 

Humans have known that for a while, which is why the portholes on the sides of ships and submarines are round. Circles maintain the integrity of the ship’s holes while corners in window panes allow stress to concentrate in particular areas. 

On top of all this, there are ribs that run perpendicular to the base grid, which reinforce the overall structure. 

Here’s the interesting part. Every other port hole has an X that reinforces the opening. Why not every opening? Because of mathematics and engineering and stuff, adding more reinforcement, wouldn’t actually add any more structural integrity. It’s like reaching a level cap, you can put more points into structure but you’re just wasting resources. The sponge, one of the most primitive animals on earth, figured out how to maximize efficiency in creating a structurally sound skeleton. 

Dr. Peter Fratzl 3D printed plastic cylinders that were inspired by the flower basket’s design and found that its was an extremely efficient design. Light, minimal, and strong. The design may spire building designs in the future so as to maximize durability and minimize waste.