Tag: alghe

Seven little lessons to rediscover our everyday life.
Seven days for the Creation… of a new perspective.

DAY 5 – THE ANIMALS OF WATER AND HEAVENS

The well-known detail: Around April-May, when plants become luxuriant again after winter hibernation, for many people the nightmare starts again: rhinitis, asthma, conjunctivitis. If you don’t know anyone who is allergic to pollens, maybe you are the one: in Italy, about one person out of five suffers from this chronic disease.

Dandelion seed – photography by Matthias Kabel

The background: Pollens cause the majority of allergies, but it is wrong to assume that these tiny grains are the only little creatures flying in the wind.

In 1910 some German scholars had already discovered some algae that live in the air; in the 1960s Malcolm Brown of the University of Austin, Texas, noticed that some types of clouds contained certain species of algae along with many other microbes.
Actually, a beautiful and seemingly clear sky is not only crossed by flocks of birds: to date, 1,000 species of bacteria (with a concentration of about 500 per m³), 40,000 varieties of fungal spores and hundreds of algae have been detected in the air, along with mosses, protozoans and liverworts.
Not to mention the most minute insects or those spiders that produce a spider’s web and let it swing until a draught lifts them in flight and then drops them off many miles away.

Aerobiologists, who study this biodiversity throbbing in the atmosphere, use the term ‘aeroplankton’ to define these floating organic particles as a whole, by analogy with the floating aquatic organisms carried by sea currents or freshwater pools.
Aeroplankton literally means “wandering in the air”: although unable to fly autonomously, some of these living creatures eat, evacuate and even reproduce in the sky.

The Fifth Lesson: Try and imagine that the sky is like the sea. Trees and plants grow attached to the seabed, mammals and other land creatures crawl and walk over them. We are also there, submerged under thousands of meters of an ethereal substance, where countless tiny creatures frantically move. Above the surface of this enormous ocean that covers everything, nothing is left but the sidereal cold.
This image – which is not so visionary, as we have learned – may not provide a relief against allergy symptoms … but our small daily problems are going to be less burdensome when looked at from this perspective, bearing in mind that we are part of a strange, absurd, gigantic bubble in which everything is impregnated with life.

This post is part of the series ILLUSTRATI GENESIS:
– Day 1 & 2
– Day 3
– Day 4
– Day 5 (this article)

Abbiamo già parlato dell’agnello vegetale, fantasioso ibrido di pianta e mammifero. Ma se l’agnello vegetale è una leggenda fantastica, la Elysia chlorotica è realtà.

Questo mollusco marino, studiato per vent’anni da Sidney Pierce, biologo all’Università della Florida del Sud a Tampa, ha lasciato molti scienziati di stucco: la sua evoluzione l’ha portato infatti ad “appropriarsi” di un procedimento di nutrizione finora riscontrato esclusivamente nelle piante – la fotosintesi clorofilliana.

Non soltanto questa specie di lumaca dei fondali marini riesce a trasformare la luce del sole in energia (cosa che soltanto le piante sono in grado di fare), ma sembra che assuma questa facoltà dalle alghe che ingerisce.

Originari delle paludi salate del New England e del Canada, questi animali si sono appropriati dei geni responsabili della produzione di clorofilla presenti nelle alghe che costituiscono la loro dieta, assieme ad alcune parti di cellule chiamate cloroplasti. I progenitori hanno quindi passato questo patrimonio genetico alle nuove generazioni, in modo che basta a un nuovo nato un unico pasto di alghe per rubare i cloroplasti ed acquisire così questi incredibili “superpoteri”.

Raccolte e tenute in un acquario per mesi, le lumachine sono in grado di sopravvivere senza cibo, finché una luce assicura loro il giusto apporto energetico. Così, in mare, possono sopportare lunghe “carestie” di alghe semplicemente cibandosi dei raggi del sole. Che l’evoluzione fosse creativa e sorprendente si sapeva. Ma un animale che produce clorofilla e si comporta da pianta supera di gran lunga le aspettative degli scienziati più fantasiosi.