One of the most common misconceptions about evolution is that it is goal-oriented.
You hear it all the time. Giraffes evolved longer necks so they could reach foliage higher up in tree branches -- as if some poor short-necked giraffes were trundling about on the African savanna looking longingly up into the canopy and thinking, "Wow, that looks amazing," so their kids were born with longer necks. It becomes even more insidious when you start talking about human evolution, because the way it's often presented is that waaaaaay back you had something like a jellyfish that evolved into something like a worm, and then into a primitive fish, into an amphibian, into a reptile, into a proto-mammal, into true mammals then primates then...
... us. Sitting, of course, on the very top as befits the pinnacle of evolution, as if all along we're what the whole process had been aiming at.
This misses the boat in several very important ways. One is that this linear view of evolution is simply wrong. Evolution causes repeated branching; in fact, in our own lineage, many of the basic body plans we have today (flatworms, roundworms, jellyfish, annelids, mollusks, echinoderms, arthropods, and primitive vertebrates) all arose at around the same time, during what's called the Cambrian explosion. During the intervening 540-million-odd years since that happened, some of the branches of the tree of life have changed a great deal more than others; but all living things on Earth have exactly the same length of evolutionary history.
A really critical way that the teleological model for evolution fails is that it misses completely how evolution actually works. Natural selection isn't forward-looking at all; it operates by the environment selecting the forms that have the highest survival and reproductive potential now, irrespective of what the conditions might be a week from Tuesday. It is very much the Law of Whatever Works, and what works today might not work at all if conditions change -- something we should pay attention to apropos of climate change.
A third problem is the perception that evolution always leads to higher complexity, strength, and intelligence. None of these are true. Consider that insects, especially beetles, are the most numerous and diverse animals on Earth by far -- both species-wise, and individual-for-individual, insects outnumber all other animals put together. Sometimes simplicity has a higher survival advantage than complexity does, and -- to judge by the natural world, and even a significant fraction of the human part of it -- I'm not convinced that intelligence is always an advantage, either.
As a good example of the advantage of simplicity -- and the reason the topic comes up today -- consider the little plant species Balanophora fungosa. It's found in warm, moist forests in Taiwan, Japan, and Okinawa, and on first glance it looks like a strange mushroom. Balanophora is in the family Balanophoraceae, which comprises sixteen genera and is somewhat tentatively placed in order Santalales along with more familiar plants like sandalwood and mistletoe. All the members of Balanophoraceae are obligate parasites, living off the roots of very specific species of trees.
Where it gets interesting is that Balanophora has done what superficially looks like evolution in reverse. It's lost its ability to produce chlorophyll; it has no conventional root system. Most of the plant kingdom have on the order of two hundred genes whose job it is to produce and operate plastids, the pigment-containing organelles that include chloroplasts; Balanophora has reduced that number to twenty. Many species in Balanophoraceae produce seeds without fertilization, obviating the need for flowers.
What's curious is that these odd little plants have been around for a long time. They branched off from the rest of the plant kingdom in the mid-Cretaceous period, something like a hundred million years ago, and have been quietly doing their thing ever since, gradually evolving to jettison structures (and even genes) they don't need along the way. "Balanophora has lost much of what defines it as a plant, but retained enough to function as a parasite," said Petra Svetlikova, of the Okinawa Institute of Science and Technology, who led the study. "It's a fascinating example of how something so strange can evolve from an ancestor that looked like a normal plant with leaves and a normal root system."
Because of its extreme specialization, both in terms of habitat and host species, Balanophora is threatened by habitat change. "Most known habitats of Balanophora are protected in Okinawa, but the populations face extinction by logging and unauthorized collection," Svetlikova said. "We hope to learn as much as we can about this fantastic, ancient plant before it's too late. It serves as a reminder of how evolution continues to surprise us."
So there you have some cool research about an evolutionary holdout from a hundred-million-year-old split in the tree of life. Here, simplicity, not complexity, seems to have been the key to its long survival. One can only hope that this strange little plant hasn't lasted so long only to reach the end because of us.
