According to this recent TED talk given by Jonathan Drori, life really is all about the birds and the bees, with a lot of help from flowers. Flowering plants, of which there are at least a quarter of a million known species, have evolved to develop fascinating traits in order to reproduce. Flowers are difficult to produce and the endeavor requires a lot of energy and resources. So why do they bother? Drori says that, like so many other things in the world, it all boils down to sexual reproduction. Plants can reproduce by themselves through self-pollination, but sexual reproduction is the means by which they spread their genes to mix with other plants in order to keep up with evolution and adapt to environmental niches.
Sexual reproduction requires the transference of pollen, a powder-like substance that contains male gametes, to other plants. Amazingly, there are as many kinds of pollen as there are flowering plants. Many types of plants, like the grasses and trees that produce hay fever, reproduce through wind-pollination. This process is inefficient because it requires plants to release massive amounts of pollen to get the job done. A more effective method is through a symbiotic process by which flowering plants transfer pollen to insects and birds in exchange for nectar. These pollinators in turn carry the pollen directly to other plants.
Symbiosis has led to beautiful adaptations like the Hummingbird Hawk-moth (Macroglossum stellatarum), which looks remarkably like a hummingbird while feeding on flowers. It has also produced unique physical traits in flowering plants that aid them in attracting insects and birds to “do their bidding.” These tools of seduction include “landing strips,” markings on petals that guide an insect to a flower, and the anthers on a lily, which are cleverly designed to flip up and knock the insect on its back, covering it in pollen.
Among the 20,000 known species of the orchid, there are a variety of unique traits. One type of orchid appears to have jaw-like petals that cover an insect in pollen as it crawls through them to get to the flower’s precious nectar. Another, the Madagascar Star Orchid, or “Darwin’s Orchid” (Angraecum sesquipedale), has a long nectar tube only accessible by an insect with an equally long proboscis. Darwin himself studied the flower and notably predicted that an insect capable of accessing this tube must have coevolved with the species. Watch the video and you will see the one with just the right proboscis for the job.
Since nectar is such a valuable commodity, some species of orchids have developed traits to help them trick pollinators into thinking they have it when they actually do not. They are able to lure insects in because they look like species that do have nectar. Other species of orchids use different methods of deception by exhibiting characteristics that are particularly attractive to a certain type of pollinator, like a pair of black dots that to a male insect look like two female insects resting on a flower, or a glossy metallic surface reminiscent of a beetle’s shell. Still others in part or whole resemble the form of an insect, like an orchid with a petal reminiscent of a bee. Bees flying by catch sight of the petal and, thinking it’s another bee, try to fight it, knocking it about and picking up the flower’s pollen in the process. In an especially devious turn, this same orchid does not offer nectar but strongly resembles another species that does.
Scent is another source of attraction. Ylang-ylang (Cananga odorata), a rather unremarkable looking plant, has an incredibly enticing smell used in many perfumes that is irresistible to insects. A very different species, the Dead horse arum (Helicodiceros muscivorus), is a lily that has evolved to look like carrion. Though it smells horrible and has no food to offer, blow-flies love it and lay their eggs inside it.
Other species of flowering plants use heat to attract insects. The Arum maculatum is a type of lily that can heat up to 15 degrees above ambient temperature. Flies are drawn to the heat and become trapped inside the flower. Once inside they drink the nectar and become covered in pollen. The flower’s bristles eventually wilt and release the flies. Philodendron selloum flowers for two days during which it maintains a constant temperature of 115 degrees with an internal thermo-regulation mechanism. It fuels this process by metabolizing fat, like mammals, rather than starch. Some beetles mate at exactly that temperature and will get inside the flower to do so, becoming covered in pollen in the process.
Color also plays an important role. In tropical regions, bird and butterflies pollinate flowers that are red because, like humans, they see the red, blue, green spectrum and are attracted to the color. Insects, however, see the green, blue, ultraviolet spectrum. Drori conducted a fascinating experiment in order to see what attracts insects to certain flowers. He photographed a Helianthemum, a small yellow flower, and compared several images of it. One image shows the flower in natural light, the way humans see it, while another shows it with the red removed, the color insects cannot see. Then Drori used an ultraviolet filter and a long exposure to produce an image depicting the flower in stark contrast to the background, looking similar to a bull’s eye. One could imagine it would be difficult for a bee to miss it. Not all yellow flowers have this property and, for comparison’s sake, Drori also shows an image of a flower that blends into the background. He notes that the flower could be used as the basis of a sunscreen, which works similarly by absorbing ultraviolet light.
This experiment ends on an intriguing and poetic note. Apparently, the main use of ultraviolet filters is to allow astronomers to take pictures of the clouds surrounding the planet Venus. Venus is also the Roman goddess of love and fertility. Drori notes that while flowers have exerted a great deal of effort to get insects to do their bidding, they have also implicated the rest of us in the process. Flowers have “managed to persuade us to plant great fields full of them and give them to each other at times of birth and death and particularly at marriage, which, when you think of it, is the moment that sort of encapsulates the sort of transfer of genetic material from one organism to another.”
This guest post is by Shannon Leahy, ASLA 2011 Summer Intern.
In The Agile City: Building Well-being and Wealth in an Era of Climate Change, James S. Russell, architecture columnist for Bloomberg News, argues against taking a mainstream, business-as-usual-approach to addressing climate change in the U.S. The current global warming debate focuses on harnessing “alternative energies” strategies, like hydrogen-powered cars and biofuels, clean coal, and reinvented nuclear that Russell calls speculative technologies that may not prove viable, require significant investments and have large environmental effects. He proposes a different approach, one that could have manifold benefits and achieve faster and more effective results than making massive alternative-energy investments that amount to tax gimmicks. There is just one sticking point: they would require the U.S. to move away from the “normalcy” of overconsumption.
Russell’s solution for adapting to climate change and achieving carbon neutrality is based on proven efficiency measures and some renewable energy. He targets buildings and transportation, the two largest sources of U.S. greenhouse gas emissions that respectively account for 40 percent and 28 percent of emissions. Addressing them simultaneously with denser, energy conservation-oriented and transit-centered development, Russell says, could result in more agile cities, those that are able to adapt to constant change, simultaneously reducing greenhouse gas emissions while coping with climate-change effects.
The agile city would evolve out of innovative policies that “deploy regulations straightforwardly, balancing them with incentives. Rules will reward performance (energy, water, and emissions saved) rather than prescribing what lightbulbs we’ll use and what cars we’ll drive.” These regulations will also boost well-being and produce economic values that gross domestic product (GDP) fails to measure, like increased real estate values from repaired natural systems and health care costs saved from reduced rates of cancer.
Rather than taking drastic measures like wiping out suburbia and converting it to a traditional city or inventing the perfect “supercar,” these regulations would engage sensible and relatively low-tech strategies to retrofit, repurpose, and reinvent the current landscape of megaburbs – a viral form of “suburbia on steroids” that requires high energy and resource use. New development patterns would create “mutt-like” urban hybrids with multifamily and mixed-use buildings clustered along transit corridors. Buildings could harvest natural sources of sun, shade, fresh air, daylight and cooling with updates to traditional climate-responsive technologies rather than requiring expensive and complex mechanical systems. Transit corridors could offer “prosaic auto alternatives that a great number of people can use,” like bike lanes, rationalized bus routes, and rail systems. As communities become denser and shift away from automobile dependence, the leftover asphalt acreage from roads and parking lots could convert to space for natural systems like suburban forests and wetland restoration.
Russell believes the U.S. can craft the policies and develop a growth machine that supports these endeavors with fairly straightforward regulatory measures, but they will require a significant shift in cultural attitudes. The current growth machine creates dysfunctional sprawl through the way real estate is financed, housing subsidies are distributed, transportation is provided, and resources like water are obtained, distributed, and disposed of in communities. This system, once supposedly intended to provide affordable housing, now forces people to move continuously further out from urban centers, resulting in a need for ever-increasing taxes and resource consumption. While new regulations could spur new development patterns, Americans, who have traditionally equated private property ownership with wealth and independence and continue to buy into the current system, would have to let go of old habits. Can megaburbs embrace big-city density and diversity, so long anathema in suburbs?
Russell thinks the government can encourage people to embrace new attitudes toward ownership and community by taking a harder line on land use policy, construction techniques, and driving. Rather than allowing private property rights to trump the greater good of the public, Russell believes government at all scales must stop basing growth on the heedless accumulation of individual investments and try to develop a land ethos based on community values. He wants to encourage Americans to adopt new ideas about ownership that would support strategies by which communities act in tandem to protect the land they share, like land trusts and mitigation banks, especially in places that are at the greatest risk of natural disasters.
He also wants to stop promoting tax benefits and subsidies that encourage funding for a limited menu of obsolete buildings and only benefit speculators and wealthy homeowners. He says to forego current incentives, like forgiving capital gains taxes on the sale of homes, and introducing new ones that would discourage people from treating their house as “investment vehicles” rather than homes. For instance, he suggests only allowing interest deductions on home-equity loans when loan proceeds go to fixing up houses, especially to make them more energy efficient. He also wants to promote tax benefits and direct subsidies that encourage builder and designer innovation and reward homes that are smaller, more efficient, and shore up existing communities and repair environmental damage.
As far as transportation goes, Russell says it is imperative to put public transportation infrastructure in place first to get people out of their cars. In order to finance this effort, he wants to banish the billion dollar beltways and divert the funding from taxes that currently subsidize roads, cars, and gas to support bus and rail systems. He suggests a 25 cent rise in gas tax, called a “mobility fee” to raise $305 billion over the next 10 years for new public transportation infrastructure. To provide further disincentive for driving, he also suggests a series of “pay as you go” fees that would provide compensation for automobile-induced pollution. These fees would include raised pump fees, additional tolls, and congestion fees.
These policies could prove a hard sell to Americans who generally dislike the idea of government actively organizing, promoting, and controlling land use. Russell provides a variety of examples and case studies to sell the benefits of low-carbon living and dispel the myth that a green economy will constrain individual enterprise. He claims he is not advocating for “faith-based greening” and “do-gooder agendas”, but rather for strategies that will simultaneously build well-being and wealth. Aware of the fact that many people believe that measures like carbon or mobility taxes will deprive people of income, Russell wants to assure them that “an agile city doesn’t simply impose new burdens but shifts incentives and disincentives (especially growth machine ones) that are more productive environmentally and economically.”
He believes the new growth machine would drive a green economy that could replace the U.S.’s unstable growth model built on short-term economic cycles and the consumption of finite resources. It would respect the limits of growth the current model wants to ignore, thereby avoiding resource shortages and the destruction of natural systems that can no longer support human endeavors. It would also support a different type of growth, one that recognizes that faster-growing cities are not necessarily wealthier: “countries can grow in wealth without growing in population and, by implication, without increasing consumption; slow growth with careful stewardship of resources could pay off.” Cities with local food economies, for example, benefit from high-quality, organic, locally-produced food that thrives in the uniqueness of a given locale’s climate and soils. This food is exchanged through personal transactions that depend less heavily on transportation energy and unsustainable manufacturing practices. Plus, locally grown crops can sustain rural places trying to compete in the hemispheric, commodity-agriculture economy.
Russell demonstrates that there are manifold benefits to connecting wealth to well-being with a triple bottom line approach to ensuring economic, environmental, and social value. But is America ready to make the significant cultural shift towards a post-consumption economy? Russell’s approach may be based on simplified regulatory measures and low-tech strategies, but, as he notes, it will require answering complex questions: “The big decisions will ultimately be ours as a society to make: What kind of people do we want to be? What kind of place do we want to have in the world? What resources are we conserving? What natural environments are we leaving less sullied for our children?”
KCAP Architects & Planners presented their vision for NEO Brussels, the redevelopment of the Heysel plateau, to the political arena, the press and the public. The team, KCAP working together with advisors Arup and Fakton, won the international design competition in September 2010. The area is one of the most strategic locations in the Brussels [...] → Continue Reading KCAP Architects & Planners present vision for NEO Brussels