The frilly collars of some lizards, for example, could become very large and exaggerated to gather water in this way. In a warming planet, endothermic animals [those that generate their own heat] may have a hard time, so birds in warmer climates may lose contour feathers to prevent overheating, and mammals may lose most fur. In this scenario, genetic engineering, biotechnology and the influence of human culture could redirect evolution down radically different paths, from mosquitoes that contain gene drives to mechanical pollinator drones.
The antlers of a deer could one day take on a new purpose Credit: Emmanuel Lafont. However, there are alternative paths for future evolution: for example, our more enlightened descendants may decide to rewild nature and let natural evolution pursue its course, or humans could become extinct which was the scenario of After Man. Extinction in particular can lead to sweeping evolutionary innovation.
In essence, a mass extinction resets the evolutionary clock, argues Ward. It made space for dinosaurs to evolve and take over as the dominant land animals, an outcome perhaps as unlikely and unexpected as the take-over by mammals when they replaced dinosaurs after the Cretaceous-Tertiary mass extinction.
This article is part of a BBC Future series about the long view of our world , which aims to stand back from the daily news cycle and widen the lens of our current place in time. That changed forever with the Great Oxidation Event, around 2. With enough time, strange and unprecedented combinations are not impossible Credit: Emmanuel Lafont. So, if humans die off, how wild and sophisticated could things get million years from now? Could we see trees starting to walk, or feasting on animals after killing them with toxic fumes or poisonous darts?
Could sea life change, with spiders taking to the water, using their webs to net sardines, while fish learn to fly so they can feed on insects and birds? Could deep-sea animals project bright holograms of themselves to fool predators, attract prey or impress potential mates?
Could we also see organisms take up residence in previously underexplored habitats: for example, giant, lightweight poisonous fungi floating in mid-air like an aerial jellyfish, entangling and consuming anything they bump into? Or could insects and spiders build silk nests in the clouds and feed on photosynthesising organisms in the sky? And if plants or microbes evolved something like solar panels to track and concentrate sunlight, could green oases of life thrive on frigid glaciers?
None of these fantastical creatures sound impossible, says Aktipis. A lot of them are based on what already exists in nature: there are seafaring and gliding spiders, there is microbial life in the clouds, and deep sea anglerfish dangle bioluminescent balls in front of them to attract prey. Some populations of killer whales and catfish can beach to hunt for animals on the shoreline, and small independent oases of life thrive on ice where there are residues of cryoconite , a black dust made up of soot, rock and microbes.
After all, we already have carnivorous plants like the Venus flytrap. She also points to the existence of spiders that eat fish , and says that cloud-dwelling microbes could possibly evolve from the multitude of tiny organisms known as Prochlorococcus that live in the uppermost layers of the ocean. Paleontologists have much more trouble with fossil species, because the organisms are no longer around to breed!
All that can be done is to match up shells or imprints that look almost identical and then assume that they represent a species. Paleontologists are sure that the fossil record is biased.
That means that some kinds of organisms are much scarcer as fossils than they were when they were alive. Other kinds of organisms are much better represented by fossils. Animals with hard shells and skeletons are represented well in the fossil record. On the other hand, soft-bodied animals are probably represented very poorly. It's likely that most soft-bodied species that ever existed are gone forever without a trace. Land animals are probably very poorly represented as well. For example, most animals that are now alive, or ever have lived, are insects, but the fossil record of insects is poor.
Skip to main content. K-5 GeoSource. PDF version. Learn More. Then, of course, there are those times that really leave us scratching our heads. And why do men have nipples? Evolution is all about creatures gradually adapting to their environment, right? For instance, some non-adaptive, or even detrimental, gene variants may be on the same DNA strand as a beneficial variant. By hitching a ride on the same DNA strand as the useful variant, a non-adaptive gene can quickly spread throughout a population.
Some of these mutations will be harmful, and will probably be eliminated by natural selection.
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