2. Nature exists where we live

Many wild birds on farmland

Costa Rica, where Professor Daily has researched for decades, is a small country; however, tropical forests covered 40% of the land, which makes it a treasure trove of biodiversity in which 5% of the all the species on the earth live.
Costa Rica is also known as an advanced country regarding environmental preservation, and one-fourth of the national land is nature reserves. Although the environment was once significantly damaged, people in the country realized the importance of what they were losing and created a movement to protect nature. Being attracted by its beautiful nature, people from in- and outside the country enjoy ecotourism there. The nature of Costa Rica has become an important source of tourist income.

There is little-untouched nature remaining on this earth, and Professor Daily placed a high priority on protecting such untouched nature by any means.

Gretchen's research base in Costa Rica

Gretchen's research base in Costa Rica

Professor Daily encountered a little trouble in 1995.
She was preparing 100 feed boxes with sugared water to study hummingbirds from the tropical forests remaining in farmlands and pastures in Costa Rica. However, those feed boxes also attracted dangerous Africanized honey bees, bees whose sting can kill humans.
People in the neighboring farmlands were distraught by this, and she had to stop her experiment.

She needed to think about a different way of conducting her research. She then thought that it might be better to observe birds on farmland rather than in the forest. It was hard to find birds in the forest because they were hiding under the leaves or in higher places, and she needed to guess what they were by their tweets and cries. She thought it would be easier to find birds on farmland, where she had a broader view.

On the farmland, she found a more extensive range of birds than she expected. She also had a chance to see Amazonian royal-flycatchers with their vivid colors.
Professor Daily was very surprised to see them and learned that farmlands were also precious habitats for birds. She realized that she needed to pay more attention to this because she may find something that she would not be able to find in the forest.

An Amazonian royal-flycatcher on farmland in Costa Rica

An Amazonian royal-flycatcher on farmland in Costa Rica

The theory of Island biogeography and nature as it is

Professor Daily's research was based on the assumption of island biogeography. Because nature is so broad and complex, research can provide only limited clarification. A full understanding of nature requires that we apply theories as well as conduct research. Given an isolated ecosystem, island biogeography clarified that the number of species on an island is determined by the number of species taking up residence on the island against the number of species becoming extinct.
This theory showed that the richness of variety on an island is significantly influenced by the size of the island and the distance between the island and the mainland. For example, species are less likely to become extinct on a larger island than on a smaller island, and this results in a greater number of species. An island located a larger distance from the mainland has fewer species because it is hard for new species to reach.
This theory had a significant impact on the concept of ecosystem integrity, showing that protecting biodiversity in an area requires a larger amount of nature and that the nature in the area be connected rather than separated so that more species can live there.

Having seen many wild birds on farmland in Costa Rica, however, Professor Daily wondered whether island biogeography applied to the real world.
For ease of understanding, island biogeography assumed an isolated ecosystem; however, the actual countryside ecosystem is within a biosphere inhabited by humans and influenced by human activities, which made it more complicated than the theory implied. Therefore, she thought, research on the countryside would require that we close the gap between theory and practice.
There is little-untouched nature remaining. Most of the areas on the earth, including tropical rainforest and oceans, are classified as countryside; and many species live in the countryside. Professor Daily believed that researching to protect such countryside would lead to the protection of many species. She decided, therefore, that this is what she should do.

Countryside biogeography

This prompted her to develop a theory of countryside biogeography as a new approach.
What is the influence that human involvement in nature has on biodiversity? As many of you imagine, human involvement in nature tends to damage biodiversity. However, the farmlands and pastures that humans develop may contribute to maintaining robust biodiversity in a different form.
The Countryside is characterized by a mixture of lands - farmland, pasture, forest, and residential areas - in a mosaic. It is like a group of islands of different sizes and distances from the mainland. Each fragmented area has species adjusted to the environment with some species moving between different types of areas.

This graph shows the distribution of species in the Las Cruces Forest Reserve and the surrounding areas

This graph shows the distribution of species in the Las Cruces Forest Reserve and the surrounding areas. It shows that many species live in both forests and the countryside (cropland and pasture), and some live only in the countryside.

In the 1970s, tropical rainforests in Costa Rica were transformed into coffee plantations; and while this led to the deforestation, the research carried out by Professor Daily and her team clarified that many birds, insects such as bees, and mammals such as bats have also built rich ecosystems in the plantations.
Bees on the plantations pollinate the coffee blossoms. Farmers in Costa Rica have realized the importance of nature and the organisms in it, all of which have unique roles in the ecosystems, and are now trying to protect the remaining nature in the farmlands and surrounding areas.

Concentrating on research on such countryside, Professor Daily gradually realized the importance of nature for humans.

With a bat

With a bat

3. What nature provides us

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Prof. Gretchen C. Daily

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