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The seasonal changes that we see on Tamborine Mountain are subtler than in many parts of the world, but spring is still a time of new buds, fresh green leaves, flowers, blossoms and fragrance. How do plants sense that spring has arrived and why do many plants produce coloured and fragrant flowers?

A major key in regulating plant activity is the change in length of day (ratio of light to darkness in a 24-hour period) throughout the year.

The seasons and length of day are linked because they are a result of the change in the orientation of the Earth relative to the Sun. The Earth's axis is tilted at an angle of 23.5 degrees. When the top half of the Earth tilts towards the sun it is Northern Hemisphere summer/Southern Hemisphere winter, when the lower half of the Earth tilts towards the sun it is Northern Hemisphere winter/Southern Hemisphere summer. Days are longer in summer and shorter in winter.

Photoperiodism is the term used to describe an organism's ability to detect changes in the length of day. In plants it is a complex process. The plant has to perceive the ratio of darkness to light in a 24-hour period and then determine the marginal increase of light or darkness. Plants accomplish this through photoreceptors found in their leaves.

Flowers are the reproductive part of plants; the male part is the stamen, which produces pollen. The female part is the stigma and style (together called the pistil); ovary and ovule; seeds and fruit develop in the female part of the flower. For a seed and fruit to develop pollen has to be transferred from the stamen to the stigma, this process is called pollination.

For most plants, pollen from one plant must be transferred to the stigma of another genetically different plant of the same species, in order to produce seed and fruit.

Since plants are unable to make any deliberate movements, they must involve agents such as insects, birds and bats, to move and transfer pollen from stamen to stigma.

To attract a pollinator, plants have to signal their location and readiness provide a food incentive such as pollen or nectar, ensure that the pollinator contacts and retains the pollen, and encourage pollinators who visit their own species and exclude those who do not.

Two major cues plants utilise to communicate and advertise to pollinators are through the scent and colour of flowers. The creation of fragrances in flowers is a complex biochemical process by which genetically coded enzymes convert a wide variety of compounds into volatile biochemicals, which evaporate into the air and produce fragrances which can activate genetic activity and repress stress.

Like the pollinators, we humans are so intensely attracted to the colour and scent of flowers that we actively promote their pollination and growth. In many respects it is the plants which are manipulating humans rather than the other way around.

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Why does attentiveness to nature matter? In a very fundamental sense, we are what we pay attention to. Paying heed to beauty, grace, and everyday miracles promotes a sense of possibility and coherence that runs deeper and truer than the often illusory commercial, social "realities" advanced by mainstream contemporary culture. ... Our attention is precious, and what we choose to focus it on has enormous consequences. What we choose to look at, and to listen to--these choices change the world. As Thich Nhat Hanh has pointed out, we become the bad television programs that we watch. A society that expends its energies tracking the latest doings of the celebrity couple is fundamentally distinct from one that watches for the first arriving spring migrant birds, or takes a weekend to check out insects in a mountain stream, or looks inside flowers to admire the marvelous ingenuities involved in pollination. The former tends to drag culture down to its lowest commonalities; the latter can lift us up in a sense of unity with all life. The Way of Natural History, edited by Thomas Lowe Fleischner and published by Trinity University Press (Texas)