“It looked as though God had caused it to rain stones,” were the words Tomás de Berlanga used to describe the Galapagos Islands upon discovering them. For guests, his choice of words might seem a little severe given how inhabited and well-chartered the islands are now. Back then however, the archipelago was as mysterious and sublime as venturing into outer space for these early explorers. Rewind the clock a few millennia further, and the Galapagos looked like the surface of a young and nascent Earth. In many ways, the Galapagos serves as a study of time and the creation of life. That same question that we all ask ourselves extends itself to this small cluster of islands: how did it all get here? How did it all begin? With vegetation being one of the main sources of all life, we couldn’t resist delving into a brief history of plant life in the Galapagos Islands to get to the root of these questions.
Distance & Desolation: Where Big Things Have Small Beginnings
With volcanoes spewing mounds of Earth upwards and outwards, the Galapagos became a robust assortment of islands that varied tremendously in both height and layout. This geological arrangement and its position along the equator would ultimately become the perfect mix of elements to eventually harbour life.
To start off, the Galapagos Islands are situated within the perfect “brewing space” for a peculiar array of weather patterns to develop. The interplay between hot and cold currents (from the north and the south, respectively) colliding with one another right along the equator creates a curious dynamic between the exterior air and water temperatures. These two converge in what’s called the “inversion zone” – basically the point where the cooler air hanging out above the cold waters meets with the hot air that’s hanging out above. This combination of factors ends up forming clouds that drift throughout the archipelago and end up getting caught in the highlands of the taller islands.
These ascending highlands pretty much act as geological “nets” that capture the clouds that drift across the archipelago. These barriers of earth are actually so good at capturing humidity that they manage to keep enough of it to maintain themselves (and their ecosystem) throughout the dry season in Galapagos.
And it was here, in the upper areas of the islands where clouds lingered about, that plant life slowly crept into the picture.
History of Plant Life in the Galapagos Islands: How Did It All Get Here?
There are a 552 species of plants that have been recorded in the Galapagos, with 372 of them being listed as native and 180 being endemic. The rest have been introduced. Worth noting is that the endemic number of plant species makes up a whopping 33% of all plant life in the Galapagos. This means that roughly 1/3 of the vegetation you will come across in the Galapagos is found nowhere else in the world!
Also worth noting is that 70% of the plants found throughout the islands are of South American origin. The rest of them came from the tropics.
It is believed that all of the following had a role to play in the transportation of seeds and plant life to the Galapagos (percentage indicates just how big of a role they played):
- Birds: 40%
- Humans: 32%
- Wind: 22%
- Ocean Drift: 6%
Once they arrived, however, where and how did they settle down exactly? After all, the islands were pretty desolate and uninhabitable in the first place. Going back to the presence of clouds in the highlands however, may provide us with a clue. It is believed that the creation of this humid niche allowed only a few, formidable contenders to enter the ring and dominate such an environment and make use of all the moisture available. Early species would end up prospering in the higher altitudes, as these humid spots enabled character displacement – an evolutionary process that involves the divergence of a coexisting species. Oddly enough, the humblest of all plants experienced this process in the Galapagos was the daisy. This tiny little flower eventually adapted and grew into the cloudier regions of the islands – eventually evolving into the tree which today we now recognize as scalesia. That’s right, the scalesia could in fact be referred to as a daisy tree.
Side note: Another form of character displacement came into play when it was clear that all the nutrients within these cloud forest trees could be extracted, especially when the trees began to rot. Woodpeckers were needed, but unfortunately with no woodpeckers around, the closest contender for the nutritious niche available was the finch – a small bird that eventually evolved into the species of finch which we now know as the woodpecker finch.
Alright. But then… How Did It All Manage to Survive, Given the Extreme Conditions in Galapagos?
Given how isolated and desolate the islands are, there were (and to this day, continue to be) practically zero pollinators. Consequently, the arrival of plant life to the Galapagos was a challenging one. As plants needed a pollinator to reproduce and didn’t have one, they were only left with either wind pollination or self-pollination (the latter of which became the most common). This pattern of pollinating had some rather fascinating repercussions for plant life in the Galapagos – as a result of cloning themselves via self-pollination, plants no longer had to “groom” themselves to look big, colourful and intricate to attract pollinators. Over the course of time, the flowers of these plants shrank tremendously in order to save the resources and energy that had traditionally gone into producing these showy characteristics. As a result, it is an evolutionary trait that explains why a lot of flowers in the Galapagos look rather “uninspired” when it comes to their design and colour. Fun fact: If you do manage to spot any colourful and big flowers in the Galapagos, it’s very likely they’re an introduced species.
Another influential factor was the fact that, in the Galapagos, the dry season tends to be longer than the wet season. If you think about the dry season as a form of winter (without the snow or the freezing temperatures), the plants here had to adapt and evolve in such a way that would allow them to survive these resource-strained times. As a result, hibernation does occur with plants in the Galapagos, except they manage to hibernate in some rather eccentric ways. The most common form of this hibernation is seen as plants lose their leaves, but the even rarer forms of hibernation include losing chlorophyll (which is when plants completely turn themselves red, or yellow) or – given how extreme the conditions are in the Galapagos – plants simply kill themselves but produce a lot of seeds for the following rainy season.