Robert Payne studied
pisaster ochraceous starfish
, which were at the top of the food chain and ate many organisms in the ocean. Payne went and threw out all the starfish from off of rocks hoping to increase the number of species on the rock by removing the predator.
What happened when Dr Paine threw all the starfish out of the ecosystem?
But it changed completely after Paine banished the starfish. The barnacles that the sea star (Pisaster ochraceus)
usually ate advanced through the predator-free zone
, and were later replaced by mussels. These invaders crowded out the algae and limpets, which fled for less competitive pastures.
What did Robert Paine do with the purple star fish?
Paine found great value in deliberately disrupting an environment in the interest of science, as he did on Makah Bay, when he threw the predator starfish into the waves, away from the shore. “
Experimental manipulation
is not only more interesting, it’s much more fun,” he told The Seattle Times in 2013.
How did Paine test his hypothesis about starfish?
Paine
realized that the starfish exerted their strong effects primarily by keeping the mussels in check
. … Paine’s starfish-tossing was strong confirmation of the HSS hypothesis that predators exerted control from the top down. But this was just one experiment with one predator in one spot on the Pacific Coast.
What did Paine develop?
| Robert T. Paine | Alma mater Harvard University University of Michigan | Known for keystone species concept | Awards Sewall Wright Award (1996) National Academy of Sciences International Cosmos Prize (2013) | Scientific career |
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Why did Paine throw starfish into the ocean?
Robert Payne studied pisaster ochraceous starfish, which were at the top of the food chain and ate many organisms in the ocean. Payne went and threw out all the starfish from
off of rocks hoping to increase the number of species on the rock by removing the predator
.
Do starfish eat mussels?
Ochre seastars (Pisaster ochraceus) feed
on invertebrates
, such as coral and shellfish, like the mussels pictured here. The starfish forces open the shell with suction disks on the underside of its body, and then inserts its stomach membranes through its mouth into the opening of the shell.
What happens when you remove the predator starfish from a single outcropping?
[CARROLL (narrated):] So Paine asked, what happens when you remove the predator starfish from a single outcrop? [PAINE:]
You have to surprise them, because a starfish clamps down. It takes a strong wrist and a pry bar.
What happens without sea stars?
With no sea stars around to feed on them, these
urchins will eat gluttonously
. … Sea stars are known as keystone predators. They prey upon species like urchins or mussels that can have a negative impact on the ecosystem if their populations grow too much. Sea star populations are recovering.
What was the result of Bob Paine’s experiment?
The results of Paine’s experiment were
counterintuitive
. Species diversity was much higher when Pisaster was present than when they were removed. … Pisaster maintained balance in the ecosystem by selectively eating barnacles and mussels, preventing their otherwise excessive spread. Dr.
What was Paine’s hypothesis?
Paine (1966) had observed that
the diversity of organisms in rocky intertidal ecosystems declined as the number of predators in those ecosystems decreased
. He hypothesized that some of these consumers might be playing a greater role than others in controlling the numbers of species coexisting in these communities.
What animal did Robert Paine Discover is at the top of the food chain?
To Paine,
the predatory starfish of Washington and New Zealand
were “keystones” in the structure of intertidal communities. Just as the stone at the apex of an arch is necessary for the stability of the structure, these apex predators at the top of the food web are critical to the diversity of an ecosystem.
Which is an example of bottom up control?
An example of bottom-up control would be
nutrient driven changes to seagrass ecosystems
. In the northern Gulf of Mexico increases in nutrient levels to seagrass meadows from land runoff can cause increased growth of the epiphytes that grow on seagrass blades.
What is missing from the bottom up explanation?
What is missing from the “bottom up explanation”? the bottom up explanation did not explain why
herbivore populations do not grow large enough to eat all of the producers
. Why was it important for Paine to record the number of different species as well as the overall number of animals on the rock outcrop?
Are barnacles a keystone species?
Almost all examples of keystone species are animals that have a huge influence on food webs. The way these animals influence food webs varies from habitat to habitat. A keystone species is often a
predator
. … These sea stars are a major predator of mussels and barnacles on Tatoosh Island.
Why is the world truly green?
For decades, the most accepted answer has been that
predators control herbivores
, allowing plants to flourish. … For decades, the prevailing scientific belief has been that our world is green thanks to predators limiting the abundance of herbivores, which in turn allows plants to thrive.
