THE PROLIFIC AFTERLIFE ARTICLE REVIEW
Article Title: The Prolific Afterlife
Author/Source: Crispin T. S. Little
A: List the major ideas, concepts or key points- point by point
B: Summarize the AUTHOR’s main point or idea- at LEAST 1-2 paragraphs
In 1987, Craig Smith and his group were in an expedition mapping the sea floor in Santa Catalina Basin. On the final dive, there was an object detected by sonar, which was found to be a carcass of a whale. The skeleton held many organisms yet discovered or found in unusual environments. The skeletons seemed to have drawn in chemosynthetic bacteria, which can make energy out of non organic chemicals, which are sometimes the basis of an ecosystem. Smith and his group decided to experiment in 1992. They discovered that the whale-fallouts had 3 stages, the mobile scavenger stage, the enrichment opportunist stage, and the sulfophilic stage. Since the discovery, researchers suspected that communities existed earlier than the first whales, reptiles such as the plesiosaur.
C: Write a reaction paragraph to the article stating your own thoughts on the topic,using specific citations from the article to support your views
After reading the article,knowing that whale skeletons can build a community under the sea, it makes me think that whales are not only harmful to organisms but can help other fishies as well. The whale skeletons can build homes for other fish and I think further experiments and research of the whale fall outs can help us understand the ecology and evolutionary history of whale falls. i think if we study more about it we can find out alot more .
Article Title: The Prolific Afterlife
Author/Source: Crispin T. S. Little
A: List the major ideas, concepts or key points- point by point
- In an expedition in 1987, the Alvin was mapping the seafloor in Santa Catalina Basin.
- On final dive, the sonar detected an object on the seafloor down 1,240 meters under.
- It revealed a large whale skeleton buried in sediment.
- The skeleton teemed with life, worms, clams, snails, limpets and microbial mats where occupying it.
- Craig Smith and his team went back to study the skeleton, to find species that were previously unknown to science and some that have been observed in unusual environments.
- Investigators documented dozens of communities supported by sunken whale carcasses, described more than 400 species living in or around the skeleton. 30 have not been seen anywhere else.
- Research sketched out a picture of how the communities of the whale-fall works and how they evolved.
- Hint of dead whales being hosts of animal communities came in 1854, when a zoologist found a new mussel from the burrows of whale blubber off the Cape of Good Hope in South Africa.
- From the 1960s onward, an increasing number of whale skulls and other bones were attached with a new mollusk species.
- Not only were the mussels found, but unknown species of limpets were found
- Limpets are snail-like mollusks with conical shells
- It wasn't until 1987, that the novelty of sunken dead whales became clear
- Mollusk species found by Craig and his team were interesting.
- Clams and mussels belong to groups known to have chemosynthetic bacteria. It can draw energy from inorganic chemicals. They sometimes are the basis of an ecosystem.
- The mollusks were known only from other chemosynthesis based sites.
- Similarities led Smith and his group to suggest in 1989 that the skeletons of the whales are the stepping stones for deep sea animals to spread one chemosynthetic community to another. Question on whether they can move between communities from one generation to the next, or on a longer timescale is still a question today.
- Smith experimented with whale-fall communities in 1992.
- They took whales washed up on the California coast and towed them out to sea and sunk them. They visited the carcasses in regular intervals.
- The whale falls go through 3 ecological stages
- 1. Mobile scavenger stage- whale carcass arrives on sea floor, hagfish tunnel through the meat and sharks take bigger bites. This strips away the bulk of the whale.
- 2.Enrichment opportunist stage- 2 years long, high-density through low-diversity communities of animals colonize sediments surrounding whale skeletons and the exposed bones.
- 3.Sulfophilic stage-bacteria anaerobically break down lipids contained in bones. Microorganisms use SO4 (dissolved sulfate) instead of O2 as their source of oxygen.
- Using data, estimating that 69,000 whales die every year, Smith and his group guessed that there is 690,000 skeletons of 9 of the largest whale species in the world. The distance from each whale would be 12km. Spacing may be close enough for larvae to disperse from one site to another.
- Newer studies suggest that a consistent group of organisms depend of the whale fallouts. The stages in Santa Catalina were not apparent.
- Discrepancies may include, the experimental sites selected were oxygen poor, reducing decomposing rates. Activities of the worm Osedax, which tunnel through the whale bones to optain lipids, proteins or both. The tunneling destroys the whale bones and speeds up the sulfophilic stage for the skeleton.
- Natural question- when and how have ecosystems evolved that seem to depend on the hale carcasses for their existence?
- Fossil whales have been found in the past 150 years, only in 1998 that the ancient whale-fall communities were recognized in Oligocene (34-23 million years ago). Fossils from the Miocence (23-5 million years ago) were found in CA and 3 sites in Japan. All the communities were recognized as such by presence of mollusk fossils.
- 2006, Steffen Kiel pointed out that early whale-fall communities from Eocene and the Oligocene were dominated by clams.
- Researchers concluded that earlier whales were not large enough to host sulfophilic communities.
- Discovery of whale skeletons that had vesicomyid clams shows that lipid content in whale bones increased the past 20 million years.
- Since the discovery of whale falls, researches suspected that similar communities existed earlier than the first whales.
- The idea that reptiles also created communities boosted in 1994, when Osteopella was found in a turtle bone in Eocence sediments. Discovery demonstrated that whale fall limpets were able to live on reptile bones.
- 2008, research groups from Japan and Poland discovered bones of plesiosaur skeletons. Scientists suggested that the plesiosuars were able to support a community. The interior of the bones looked a lot like the modern whale bones.
- More finds of active and fossil bones will be necessary to reveal ecology and evolutionary history of whale falls, and if they're linked to those of reptile falls.
B: Summarize the AUTHOR’s main point or idea- at LEAST 1-2 paragraphs
In 1987, Craig Smith and his group were in an expedition mapping the sea floor in Santa Catalina Basin. On the final dive, there was an object detected by sonar, which was found to be a carcass of a whale. The skeleton held many organisms yet discovered or found in unusual environments. The skeletons seemed to have drawn in chemosynthetic bacteria, which can make energy out of non organic chemicals, which are sometimes the basis of an ecosystem. Smith and his group decided to experiment in 1992. They discovered that the whale-fallouts had 3 stages, the mobile scavenger stage, the enrichment opportunist stage, and the sulfophilic stage. Since the discovery, researchers suspected that communities existed earlier than the first whales, reptiles such as the plesiosaur.
C: Write a reaction paragraph to the article stating your own thoughts on the topic,using specific citations from the article to support your views
After reading the article,knowing that whale skeletons can build a community under the sea, it makes me think that whales are not only harmful to organisms but can help other fishies as well. The whale skeletons can build homes for other fish and I think further experiments and research of the whale fall outs can help us understand the ecology and evolutionary history of whale falls. i think if we study more about it we can find out alot more .