Fish emerged out of primitive life forms on ancient ocean floors. Scientists aren’t sure but they probably came from starfish, tunicates or conodants (now extinct). Fish have been here for 540 million years, we humans, 2 million.
540 million years ago it was the Cambrian Era. The earth was warmer with little polar ice. No life on land yet except for bacteria that covered the desert continents. There was an abundance of shallow Cambrian seas that were relatively warm after the breakup of the supercontinent, Pannotia. This was the time of the Cambrian Explosion, when life takes off. In this cauldron of biological creativity, organisms poured forth at an accelerated and diversified rate. This is when fish came onto the scene.
The first fish were multicellular creatures with gills and a notochord. They swam. They ate. They reproduced. While there is a long branching list of ancestors and body types of the fish, there is too, a list of attributes developed by the fish over this immense period of time. This list includes jaws, bones, teeth, muscles, scales, cartilage, gills, eyes, ears, lungs, limbs and complex neural pathways. You can recognize some of these in your own body.
All these developments enhanced the life of a fish. Their world of movement, sight, energy and sound deepened. A certain kind of fish, the teleost, reached new levels of complexity in their fins and jaws and mostly populate our oceans today. It was the fish that crawled out of the sea into the line of amphibians, reptiles and mammals. As fish became more and more prosperous and numerous they filled the oceans in great numbers encircling the planet. 540 million years is a long time. All the while, throughout the ages fish survived and prospered.
When humans come onto the scene the oceans are full of fish.
Salmon journeyed down mountain streams and circled the northern Pacific and Atlantic oceans in great schools. Come fall rains they would crowd the rivers and streams to spawn. The only viable remaining populations of salmon are in Canada and Alaska.
Cod covered the outer banks of the continental shelves. Vast in number and relatively easy to catch they become the food of choice for many. No one could imagine their demise. They are now almost completely gone.
Swordfish and marlin populations have crashed. So has the magnificent Atlantic bluefin.
36 species of groupers populated the coral reefs of the South Pacific. They come together in vast numbers (thus the name) to spawn, making them an easy catch.
Sharks and rays roamed the oceans worldwide. They too, have greatly disappeared.
Every population, species or group of fish that we can identify has been significantly reduced. As recently as the 1950, the oceans were loaded with fish. People marveled at their numbers. Nobody ever imagined that we could reduce their populations to small remnants.
Fish populations around the world in all of the oceans have plummeted with the pressures exerted on them by us. We have come to a crossroads in the story of fish and the story of the human. The fate of fish, after 540 million years, is in the hands of humans.