TUZLU SU SALTWATER

264 Lynn Margulis, Celeste A. Asikainen & Wolfgang E. Krumbein
Antoloji / Anthology
265
relevant aspects of Earth’s surface. Life forms strive to maintain habitable local conditions. Gaia
theory specifically proposes that water regulation emerges from life itself (Harding and Margulis
2009). Earth’s organisms incessantly respond to their abiotic and biotic surroundings: temperature
change, chemical composition of air, soil, and water, light and dark conditions, mechanical
impediments (wave actions, wind, rain, snow, fire), and many other variables. And response to
water, both thirst and satiation, seems universal.
Life’s sensitivity to the quantity and the saltiness of water may be the most elemental of all senses.
Plants, animals, fungi, and all microorganisms know thirst and assess wetness. Life senses local
water levels. The universality of water detection and the response of living cells to this ubiquitous
solvent seem to reside in the properties of the lipid-protein membrane. This membrane, called a
‘semi-permeable bilayer,’ is the intact external boundary of all cells at all times. When it is breached
and its integrity is lost, the cell, whether it is a small bacterium or a large egg, dies. Once lost, the
ability to regulate the flow of material and energy through the lipid bilayer of the cell’s membrane
is irretrievable. Water leaks out. The permanent one-way loss of water out of the ruptured membrane
is a symptom that the food (material) and energy transformation have stopped. The thermodynamic
system of life halts (Schneider and Sagan 2005). This has a name: we call it death. As
soon as the self-maintaining activity of an organism ceases, its material will be replaced by an inert
puddle of carbon-hydrogen-nitrogen compounds. Identity of a life form, whether of one or more
cells, requires a continuous influx of energy and material. In the absence of self-maintenance, any
being immediately loses all signs of animation. Formerly alive matter transforms. It becomes food
for those that retained their intact membranes and, with them, the profound sense of water.
Water sensing requires at all times the ubiquitous lipid-protein cell membrane that confers identity.
‘Ion channels’ that sense and move salts are embedded in it. Most surprising to us is the set
of facts established by Ching Kung and his colleagues: fragments of membrane taken from living
cells retain properties of sensing and response to salt and water for quite a while after the cell has
died. For minutes, even hours, Kung and his colleagues ‘poke’ isolated membranes and measure
behavioural activities. Specialised proteins embedded in the outer membranes of cells recognise
familiar ‘minerals’—that is, ions in solution, such as calcium (Ca 2+ ), potassium (K + ), hydrogen ions
(H + , acidity), and hydroxyl ions (OH - , alkalinity). The membrane-channel-making proteins can
block and release the flow through them of ions in water. Some of these channels are activated by
a familiar force: touch. Mechanical stimulation, the simple bending of the membrane lipid bilayer,
blocks and/or releases the flow through it of ions in water. This block and release, underlaid by
the closing and opening of the channel by protein shape changes, responds to various stimuli.
Certain ion channels are sensitive to mechanical stimuli, including touch, blood pressure, sound,
and changes in salt concentration. A Paramecium recoils from physical impact at its head end.
Research also shows that pressure exerted on a patch of membrane can stretch it. This stretching
causes certain bacterial channels to open or close. It thins the lipid bilayer and creates a chemical
change that causes the channel to open. For living bacteria, an increase in osmotic pressure
when water rushes into the cytoplasm after a rain causes the same membrane stretching. The fact
that organisms sense water and show many behaviors that help retain it in their immediate vicinity
has had a profound effect on the collective of life. We think that the continued presence of water
on Earth for more than 3,000 million years must be attributable to life’s activities. Life’s presence
has depended on the continuation of planetary water, not on a lucky place in the sun.
Life does indeed change its environment to fit itself, as L. J. Henderson and Ian McHarg insisted.
But does the assertion that ‘any organism’ is ‘well adapted to its environment’ have any meaning?
All organisms alive today are ‘adapted’ by virtue of the fact that they live. Their ancestors have
survived from the past to the present. Gaia emerges as different organisms affect one another
and their surroundings. Through the exchange of heat, light, liquids, gases, and a huge array of
chemical elements, their salts, sugars, long polymers like starch or cellulose, and other chemical
compounds, the ‘creative fitting of health’ can be documented. McHarg notes that the trouble
and pain of an unhealthy person, family, woodland, or neighbourhood is recognisable as the
‘reductive misfit revealed in pathology,’ in which the organism-environment fit is threatened. The
biological reality of health, in contrast, depends on incessant effective communication between
the live organisms and their physical and social environments via senses.
Etel Adnan
Deniz ve Sis (2012)
Bir uçla öbür uç arasında sonsuz bir mesafe görüyorum. Bu yüzden zaman sonsuz olmalı.
Bir keresinde aya gitmiştik, uygun bir havada ve birbirimizi dünyevi ortamımızda başaramayacağımız
şekillerde sevmiştik. Ara sıra da gülmüştük.
Mikrodalga ışınları Yeryüzü’ne yağıyorlar. Beyne nüfuz edip onu sanki bir fırına çeviriyorlar.
Balıklar derine dalıyor. Adacıklar titreşiyor ve bir aşağı bir yukarı sallanıyorlar. Bu hengâme,
keyfin yanı sıra birçok soruyu da getiriyor.
Şiir, dile gelmemişe ulaşır ve onu dile gelmemiş bırakır. Tanıdıktır, edepsizce yakındır, bazı
zamanlar bunaltıcıdır, melankolik dağ sıralarının üzerindeki bulutlu gökyüzünün grisi gibi;
O, olduğu gibidir, doğasına dair bilinmezlik daima sürer ve bizim neden hâlâ bir cevap aradığımız
sorusu da.
…
Muson’un çarpık kibri yüzünden uyuyamıyoruz. Yumuşak yapraklarla kaplı havuzların üzerinde
belirsizce parlayan güneş, ruhun çılgınlığın yayılmış kederden yorgun düşmüş. Hafızanın
işlevi, geleni sonraki günlere rasgele yeniden dağıtmaktır.
…
Uzam var, o kesin, biz onun içindeyiz, ama peki zaman nerede? Değişim var ve değişim
devinimdir. Buna şüphe yok. Öyleyse değişimden soyutlanmış zaman, bir saatin ibreleriyle
temsil edilen devinimdir. Değişimin ölçüsüne biz zaman diyoruz. Ölümden, ölümcül bir
değişimden korktuğumuzdan onun her şeyin içinde ilerlemesinden de korkuyoruz. Oysa,
devinimdeki değişimden ve mucizeden hoşlanıyoruz.
Uzay manevi açıdan nötr, bir çözüm sunmuyor. Bu gezegen ise hâlâ arkadaş canlısı, dolayısıyla
kimi daha hoş tezahürlerini kucaklayabiliriz, zamanın düşüncelerimize teğet geçmesine
izin vererek. Peki ne bizi hiçbir şeyin olmamasını beklemeye itiyor?
Her bir saniye sonuncusu olabilir, bu yüzden kaygılıdır taşlar bile. Derine gömülü eski içgüdü
yeniden yüzeye çıkar. Umutsuzluk somurtuktur. Kısa kanatlı sert rüzgârlar. Cesetleri
kusan deniz. Toprak ve deniz birbiriyle çarpışır. Suların geri dönmesi için.
…
Her bir bastırılmış gözyaşı geri döner, bir dalga, kaçırılmış bir otobüs, bir fırtına olarak: sona
eren bir gün, bir günbatımı. Deniz tekrarlar kendini, bu dünyanın vaadine hazır olamayan
birinin tekrarladığı gibi.
Seçen Etel Adnan Çeviren Anita Sezgener