A pile of cells, and before that only two, united in a lucky encounter. The man shares this microscopic origin with the most colossal and minute animals, which the film-maker and Dutch photographer Jan van Ijken has now captured in time-lapse.
Becoming was born this way: van Ijken wanted to document the process of becoming from the beginning, and he decided to follow the evolution of the eggs - transparent - of Alpine newt (Ichthyosaura alpestris), an amphibian of the salamander family.How life is born
The shooting. The director collaborated with a breeder who could warn him whenever a captive-grown newt egg cell was fertilized by a male. Filming under the microscope the first cell cleavage turned out to be a race against time; and also with the following ones, the work was particularly complex.
Sometimes van Ijken came too late. At other times the cell division took place on the opposite side of the embryo, others still did not happen, or there was not the right light. What in the movie looks like the development of a single larva, is actually a collage of videos and photos of many embryos, taken in successive phases of cellular development. To condense in six minutes what Nature does in four weeks, it took six months - but if you saw the video you will agree that it was worth it.
The recognizable stages. In some ways, what is observed is not very different from what happens to human embryos. Around the end of the first minute of video (the third day of development), we note that the embryo ripples and folds back on itself: it is the process, fundamental for vertebrates, of gastrulation, a set of organized cellular movements that imprints to the embryo a first form and gives rise to a caudal extremity, a cephalic, a back and a belly in addition to the endoderm, a layer of cells that will form the digestive tract.
The embryo is called at this time blastoporo, and what we observe in the video is what will become the anus of the salamander. About 45 seconds later, the neural plate emerges, the first sketch of the central nervous system.
Around two minutes and twenty, the migration of cells towards the surface of the newt is noted: by responding to genetic instructions and signals from neighboring cells, they are preparing to form different tissues. It works: in the fourth minute there is a beating heart, and blood in circulation.
Precarious. The life filmed here in its beginnings is extremely fragile: many of the larvae followed by the photographer did not arrive at this stage, and those that develop in nature are exposed to the precarious conditions of the habitats and to the polluting substances that we pour into the rivers. When hatched, the larvae, without legs and gills, feed on plankton remaining attached to the seabed or aquatic plants. Once the limbs have been conquered, the amphibious life will officially begin.