Alfred the aetiocetid had teeth but needed a better way to capture his tiny prey.
The largest animals on the planet - the baleen whales - prey on some of the smallest. But how did their teeth evolve into the filters they use today?
Ship strikes can be deadly, as shown by this blue whale off the US northwest.
Craig Hayslip/Oregon State Univ./Flickr/Wikimedia Commons
Ships in Australian waters are getting bigger and more numerous all the time. We need a plan to help them avoid crashing into whales and other large sea creatures.
Right whales have been shown to be affected by noise pollution.
FWC Fish and Wildlife Research Institute/Flickr
The increasing use of the sea for human activities has resulted in a dramatic rise in noise levels.
Australia’s oceans are home to extraordinary marine life.
Australia has the third largest marine jurisdiction in the world, a vast ocean territory that contains important natural and biological resources. And it needs protecting.
The second-noisiest animal in the ocean, the snapping shrimp.
Dr Tullio Rossi
The oceans are filled with sounds produced by animals. However, a recent study shows that ocean sounds are diminishing due to nutrient pollution and ocean acidification.
A bloom of phytoplankton in the Barents Sea: the milky blue colour strongly suggests it contains coccolithopores.
Wikimedia/NASA Earth Observatory
Tiny organisms change ocean acidity to benefit themselves.
Coal dust can harm marine environments.
AAP Image/Dan Peled
Coal dust and oil can spread toxic chemicals hundreds of kilometres out to sea. But Australia's monitoring guidelines do not meet the standards used in countries such as the United States.
Stormwater may be a road hazard, but it can also harm marine life when it flows out to sea.
AAP Image/Paul Miller
Storms like those that lashed Australia's east coast flush pollution out to sea.
Corals north of Cairns have been hit hardest by the recent bleaching.
AAP Image/ARC Centre of Excellence for Coral Reef Studies, James Kerry
An estimated one-third of corals have now died in the parts of the Great Barrier Reef hit hardest by bleaching, meaning recovery could take years or even decades.
A study has shown that turtle hatchlings lend each other a flipper digging out of the sand to save energy.
Banco de Imagem Projeto Tamar/Flickr
New research suggests turtle hatchlings work together with clutch mates to escape their underground nests.
Coral affected by black band disease, Bahamas.
James St. John/Flickr
Infectious diseases are a normal part of ocean ecosystems, just as they are on land. But climate change is altering the oceans in ways that could make marine diseases spread farther and faster.
Plastic fragments found in dissected fish.
Algalita Marine Research and Education
Dave West from the environmental group Boomerang Alliance told Fairfax that if you've got an average seafood diet in Australia, you're probably ingesting about 11,000 plastic pieces a year. Is that right?
A Japanese fish found in Washington after hitching a ride in a boat sent across the Pacific Ocean by the 2011 tsunami.
The 2011 Japan tsunami illustrates how more marine creatures are crossing the oceans than ever before - and not all of them are friendly travellers.
Jelly invasion: is this a vision of the future for our oceans?
We know a lot about the potential negative effects of ocean acidification on marine creatures. But might some species actually benefit? The answer is yes, but this isn't necessarily a good thing.
Right whales pass on the knowledge of their migration routes.
Why are some southern right whale populations not recovering as fast as we hoped? The answer may be in their migrations.
A typical elephant shark from the Melbourne Aquarium.
Some things that develop as normal in elephant sharks and other marine life can mimic things we see in human disease. That makes these 'mutants' ideal for study to find out why things go wrong in humans.
An Indo-Pacific Man-o-war, AKA bluebottle, washed up on a beach.
Copyright L Gershwin
Blue bottles have been washing up on beaches lately, but what exactly are they? And are you really supposed to pee on their stings?
Tuna and other top predators could run out of food in warming seas.
Tuna image from www.shutterstock.com
Over the past five years we've seen a significant increase in research on ocean acidification and warming seas, and their effect on marine life. Overall, unfortunately, the news is not good.
This common lionfish (
Pterois volitans) was sighted more than 200km further south than expected down the NSW coast by 14-year-old scuba diver Georgia Poyner. It’s one of almost 40 verified observations she has submitted to Redmap.
We know the warming seas are forcing some marine life to new waters, but we don't know much about how fast and how far they are moving. But now you can help scientists find the answers with Redmap.
Tagged male seahorses in the laboratory aquarium.
It's long been known that it's the male seahorse that gives birth to the young. But what role the father plays in the gestation is only now being revealed.