Life on Our Planet examines some of the most significant turning points in order to make sense of it. Photosynthesis, multicellular animals, skeletons and legs, and big brains were innovations that allowed life to adapt and change its environment.
Trailer for Life on Our Planet.
The relentless movement and repositioning of continents is what has shaped the world. Landmasses have clustered together to produce vast deserts and then broken apart, as they are now, to create a greater variety of environments with vastly higher diversity. The interplay of biology and geology weaves together the series.
Life on Our Planet contains some important messages regarding the nature and Future of evolution. Here are three of the most important ones we believe.
1. There is no perfect thing.
Every child knows that Natural Selection favors those who are most capable of reproducing and shapes the genetics of all species. This process of hone is not perfect, and eventually, all species will go extinct.
The evolutionary arms race between predators and prey is never-ending. Netflix
Other species, such as parasites, predators, and competitors, are constantly out to get you. The species are always evolving to keep up with the changes, but they can’t. The Red Queen of Lewis Carroll’s Through Looking Glass said: “It is difficult to stay in one place.
It’s even worse than that. Natural selection is not the only source of evolution. The random movement is responsible for a lot of change. Many traits are not advantageous but just coincidental with those that are. Some modes of speciation may be dependent on random effects.
Anchiornis. Netflix
Stephen Jay Gould, a palaeobiologist, warned against viewing all biological structures in a way that assumes they were perfectly adapted by evolution to accommodate specialized functions. Life on Our Planet sometimes adopts this adaptationist view, but usually to achieve a dramatic story.
2. The key to the Future is in the past
If you trace your family tree to about 12,000 years ago, you will be close to the origins of our species. You can go back 300,000 years and find that your great-great-grandmother lived with a chimpanzee. Around eighty million years ago, your tree merged into that of the dog.
Each species carries a heavy evolutionary burden. It’s amazing that our embryos “run through” these ancient evolutionary predecessors. Early in the development of our sources, we have the gillslits and tails of fishes.
A rhipidist fish. Netflix
The imprints left on our genes and bodies often limit how we can develop in the Future. We can’t fathom why some things “got stuck”.
No matter how large or impressive their necks are, nearly all mammals have only seven vertebrae. In contrast, birds, which are 320 million miles away, have evolved different neck bones. Parrots and swans have 10, while parrots and swans each have 26.
The more complex the development, the more interdependent components (genes and structures) become. These tend to perform more than one function. It becomes harder to improve one thing without affecting others. It’s difficult to build a higher tower using blocks from the lower levels, much like Jenga.
3. Nothing lasts forever
Five mass extinctions have marked the story of Life on Our Planet. A different event triggered each. The animals and plants of today are only the tops of vast “icebergs” that are otherwise extinct. 99% of this biodiversity is submerged and known from fossils.
There are no descendants of many once-dominant branches of the tree. Examples include the armored pterosaurs and the armored trilobites. Some species, such as the egg-laying mammal (monotremes) and the Largetooth Sawfish, are hanging on by a thin thread.
Life on Our Planet. Netflix
Episode six, which shows how wiped out most dinosaurs and 75% of all other species (including humans), is the most well-known mass extinction. However, it wasn’t even the largest. Episode two shows an unsustainable and unprecedented planktonic growth in the Late Devonian 360 million years ago. The oceans became anoxic as bacteria harvested the remains of the dead plankton. The seas became anoxic (depleted in oxygen) as a result of the plankton dying.
Even worse, 252,000,000 years ago (as seen in episode three), massive upwellings melted through the Earth’s surface over millions of square kilometers of Siberia. The ” Great Dying,” which followed, saw 96% of marine species on the planet disappear. The volcanic emissions of greenhouse CO2 increased Earth’s temperature by 10 degrees while SO2 produced acid rain, which washed entire ecosystems away.