Sponges Likely Paved the Way For All Life on Earth
by Jennifer Viegas
The seemingly lowly sponge, just by its very existence, might have paved the way for the evolution of complex life forms, including our own species, according to a new paper.
Sponges appear to have added oxygen to the deep ocean, creating an environment where more mobile, major oxygen-using animals could have evolved, holds the paper, published in the latest Nature Geoscience.
The research builds on work, presented earlier this year, which found that the most primitive sponges probably could survive in water containing very low levels of oxygen…
Also sometimes known as the Goiter Sponge, the Chalice sponge is a species of glass sponge (Order: Hexactinellida) that occurs in deep off of the western seaboard of North America. Heterochone calyx is commonly seen growing in large “forests” on the upper portions of seamounts, where currents concentrate food particles. Like most sponges H. calyx is a filter feeder and will filter the water around it for nutrients.
The Cloud Sponge, Aphrocallistes vastus, is one of the most ecologically significant sponges in the North Pacific Ocean. Due to its rigid skeleton, it is an important structural component of sponge reefs. Bigmouth sculpin (Hemitripterus bolini) deposit their eggs in the spongocoel, and juvenile golden king crabs (Lithodes aequispina) use it as a refuge…
Did you know that there is such a thing as a carnivorous sponge?
Typically, sponges feed by straining bacteria and bits of organic material from the seawater they filter through their bodies. However, carnivorous sponges snare tiny crustaceans. The species featured here are all part of the same family of sponges, the Cladorhizidae. They may look very different, but each has structures used for prey capture.
Top: the harp sponge, Chondrocladia lyra; Middle: the golfball sponge, Chondrocladia sp.; Bottom: the branched sponge, Asbestopluma.
There’s a longstanding theory which says oxygen-rich oceans were a key requirement for complex life to emerge on Earth. But a new study involving sea sponges upsets this notion, showing that primitive animals may have been able to survive with hardly any oxygen at all.
The first microbes appeared on Earth about 3.6 billion years ago, but it took an exceptionally long time for complex multicellular life to emerge — another three billion years. Perhaps not coincidentally, this also happened to be the time when levels of oxygen in the atmosphere escalated to present day concentrations of about 20%. Many scientists have thus concluded that animals needed the higher levels to survive, thrive, and evolve.
But a new study by Daniel Mills of the University of Southern Denmark in Odense suggests this may not be the case. By studying modern breadcrumb sponges, Mills has threatened this assumption, while simultaneously strengthening another.
200 Times Less…
Sea sponges may not seem animal-like, but they are among the planet’s earliest animals. They’re always multicellular and they grow from an embryo. They’ve also got complex physiological structures, including a network of channels that help draw food and water through their bodies. And based on the paleontological evidence, modern sea sponges aren’t too far removed from their ancient brethren…
A spectacular group of Venus’s Flower Basket Glass sponges (Euplectella aspergillum)with a squat lobster in the middle, photographed in the Gulf of Mexico, North.
Euplectella aspergillum is a sessile animal that protrudes from the rocky ocean bottoms. Its skeleton contains hexactine (six-rayed) siliceous spicules and in addition contains a latticework of fused siliceous spicules. This is where is gets the name “glass sponge” because quite literally it is made of glass, making it the most exquisite example of the class Hexactinellida, but also as precarious and as brittle as glass can be.
One very unique feature about the E. aspergillum is that very often you can find some abyssal shrimp within the cavity produced by the lattice structure that makes up the sponge. Sometimes young male and female shrimp enter this cavity while they are still larva and over time they begin to feed and grow. The small shrimp grow and become too large to leave the silicon cavity of the sponge. It is customary in Japanese culture to give this elegant glass sponge away as a wedding gift symbolizing the wedding vow, “Till death us do part”.
Animalia - Porifera - Hexactenellida - Lyssacinosidea - Euplectellidae - Euplectella - E. aspergillum
In the evolution of animal life on Earth, sponges have long soaked up the accolade of being the most primitive creature ever to have existed. Now it seems that their position at the very base of the tree of animal life is in jeopardy, thanks to the humble comb jelly. The finding may force us to reconsider our understanding of early animal evolution.
Unlike sponges, comb jellies (or ctenophores) have a primitive nervous system, are hungry predators and have complex cells also found in bilaterians – the group of animals, including humans, that have fronts, backs, an upside and a downside.
All animals around today split from a common lineage, about 650 million years ago. Although there is much debate about the early sequence of events, it is generally accepted that the first animals were ancestral sponges.
"When you’re learning about how animals evolved it’s always been that the last common ancestor to all living animals was probably very simple and that once the animals had a neural system and muscles they would never lose them," says Joseph Ryan at the US National Institutes of Health in Bethesda, Maryland…
First-Ever Submarine Dive on Vancouver’s “Living Fossils”: Glass Sponge Reefs
Researchers discover a seafloor oasis made of hundreds of glass sponges.
by Anne Casselman
Howe Sound, British Columbia—Through the submersible’s acrylic viewport, a large patch of glass sponges looms up from the seafloor of Howe Sound (map), a network of fjords located on Vancouver’s doorstep. The sponges glow creamy white and orange under the sub’s high-intensity lamps and extend across a 40-foot-high (12.2-meter-high) mound.
"Topside, topside, be advised we have sponge at this location," senior pilot Jeff Heaton says into his communication system from a depth of 135 ft (41.1 m).
"This is a sponge reef," says Heaton from inside the inch-thick (2.5-centimeter-thick) steel hull of the Aquarius submersible, a three-person vehicle owned and operated by Nuytco Research. “No doubt about it.”
This week, the Canadian Parks and Wilderness Society (CPAWS) and Nuytco Research mounted the first submarine expedition to the glass sponge reefs found in Georgia Strait off of Vancouver.
The expedition aims to check on the status of these sponge reefs, which currently have no protection from damage by fishing activities, and to raise awareness of their existence…
…a species of pyurid ascidian (sea squirt) that occurs off the coasts of New South Wales and Victoria, Australia. Like most tunicates P. spinifera is a filter feeder, filtering the water around it for nutrients and expelling out excess. P. spinifera ‘comes’ in a wide range of colors, ranging from white, pink, yellow, orange, and purple. The color is determined by the symbiotic sponge that covers the ascidian’s surface.
Most animals, when chased by a predator, can run away. Not so for many coral reef animals, such as sponges and corals, that are attached to a surface and can’t move away. Instead, these sessile critters (such as the liver sponge shown here) must have other types of defenses that protect them from predators. These could include structural defenses, such as hard shells or prickly spines, or chemical defenses that make them taste bad.
Studying these defense mechanisms could lead to the discovery of new medicines, tools for increasing seafood supply and safety, and new resources and industrial processes.
This white sponge (in the family Euplectellidae) is anchored to the seafloor with very long spicules. These spicules create microhabitat for very small crustaceans and worms. It is fastened to angular pillow-lava talus near the bottom of the steep talus slope flanking the cone of Axial Seamount. The amount of sediment that has accumulated suggests the cone is fairly old, and the presence of a large, long-lived, sessile organisms such as this sponge suggests the talus slope is stable.
Read about what researchers on the WesternFlyer are learning about volcanic eruptions at the deep sea Axial Seamount:
During Sunday’s dive in Hydrographer Canyon, a deep sea canyon off the NE coast of the United States, amongst the diverse coral community, our remotely operated vehicle observed a glass sponge containing cephalopod eggs. If you look closely you can see what looks to be a recent hatchling!
Another Look at the Changes on the Antarctic Sea Floor
What scientists thought would take centuries to occur is taking place in just a matter of years. “…populations of glass sponges have tripled between 2007 and 2011, allowing them to completely take over the seafloor.”
In the frigid, inky ocean depths beneath permanent ice shelves, life tends to move pretty slowly. But a recent expedition to the seafloor under a newly thawed Antarctic ice sheet has revealed an unexpected invertebrate invasion. Some of Earth’s strangest species, a group of ghostly pale sponges made of glass, have set up shop there in a hurry, upending much of what scientists know about these exotic creatures.
Thanks to changes in this ecosystem brought on by a warming climate, these gardens of glass sponges have sprouted up in only a few years, a veritable population explosion for species once thought to take decades or centuries to spread. It suggests that glass sponges could find themselves squarely on the winner’s podium when it comes to climate change.
In 2011, a team led by researchers from the Alfred Wegener Institute for Polar and Marine Research completed a new census of glass sponge growth on the seafloor underneath the Larsen Ice Shelf in Antarctica’s Weddell Sea, following up on a similar survey done in 2007. Their surprising results were published today in Current Biology…