​Great discovery, water can flow again on Mars ● Humanity uses more than a third of vertebrates ● Who invented flour from cereals, us or Neanderthals?

Big discovery: water can flow again on Mars

New images of the Red Planet released by NASA show gorge-like channels that are strikingly similar to those left behind by the melting of Antarctic ice sheets. The problem would be that both the temperature and the conditions on Mars do not allow water to exist in a solid state. And then, where do ravines come from?

One of the hypotheses proposed by a group of American researchers from NASA, Brown University in Rhode Island, and the University of Santa Cruz, California, was the hypothesis of the sublimation of carbon dioxide (direct transition from a solid state to a gaseous state) as the reason for the appearance of these unusual channels. But the sublimation hypothesis was not considered sufficient to explain their shape, position and distribution. At least, if it is not supported by other natural phenomena.

The second explanation, which was argued in a study published in the journal Science, was particularly interesting. The aforementioned experts believe that liquid water could have created such forms. Moreover, they would have done so less than a million years ago. More precisely, a maximum of 630,000 years ago. An idea that fundamentally changes all assumptions about the existence and disappearance of liquid water at least 3 billion years ago.

The secret lies in the inclination of the axis of the planet Mars. Computer simulations show that at a tilt of 35 degrees, the temperature rises above the freezing point, and the Martian ice may partially melt, allowing liquid water to reappear. And such a phenomenon would happen several times only in the last million years. Taken together, these two phenomena, sublimation on the one hand and ice melting on the other, perfectly explain, according to scientists, the existence of ravines.

If it turns out to be real, the hypothesis of American scientists will inevitably cause a discussion of the most relevant topic related to the Red Planet – the existence of life. At least theoretically, microbial life forms could survive in the Martian ice, and the melting of the latter could give a favorable impetus to the existence of hypothetical microorganisms.

But let’s get excited like the aforementioned researchers. We still have a long way to go to prove such things, and if we wait for a 35 degree axial shift of Mars, we could be waiting at least a few hundred thousand years. We’ll come by soon to see how you’re doing.

Humanity exploits more than a third of vertebrates

A team consisting of specialists from Canada, the USA, Argentina and Great Britain offers us some data and more than interesting statistics related to the human use of vertebrate life forms. Statistics that appeared in the form of a study in the journal Nature.

Thus, the cited authors show us that 14,663 species of birds, fish, mammals, reptiles or amphibians are exploited by humans in one way or another. This is about 30% of all existing species (ie about 46,755).

Of these, 55% are killed for food, and 40% are kept as pets. Only the last category, as another example, includes 4489 species of birds. In fact, birds and fish represent the most exploited animal groups, while reptiles and amphibians are at the opposite pole.

This tendency has, rather, a cultural substrate. In most cultures of the world, certain animals, such as rodents, bats, reptiles or amphibians, are considered unclean. For example, you won’t see too many people collecting or keeping mice or bats as pets.

What is really serious is that these trends do not take into account the rarity or degree of danger in which a particular species is. In fact, researchers note, 39% of exploited species are on the brink of extinction precisely because of humans. And this overexploitation will clearly have dire consequences for both biodiversity and, implicitly, humanity, the factor that started it all. Circle of life!

Who invented flour from cereals – us or the Neanderthals?

A recent archaeological discovery at the Paleolithic site of Riparo Bombrini in northern Italy sheds new light on what was known about the emergence of flour and the processing of wild grains or other plants to produce it.

These are two stone millstones discovered in the context of the Mousterian period (material culture of the Neanderthals), which show traces of starch from cereals and other as-yet-unidentified plants. Their age would be about 43,000 years, which is an additional argument in favor of their Neanderthal origin.

What is so special about this discovery is that it is the oldest of its kind. In addition, a similar discovery at the site of Grotta di Castelcivita, Campania, southern Italy, presents similar objects but in a proto-Aurignacian context, one of the earliest forms of Homo sapiens cultural expression in Europe. Except that in this case the age of the artifacts would be approximately 41,500 years. And this could apparently lead to Neanderthal advances that predate similar H. sapiens discoveries by more than a millennium.

But the problem is somewhat more complicated. First, the period from 40,000 to 45,000 years ago, at least in Italy, is extremely complex. This is a relatively short period during which three material cultures quickly replaced each other and even overlapped (the Mousterian Neanderthal culture, the Uluzian culture with an as yet unknown author, then the Proto-Aurignacian culture attributed to Homo sapiens).

Many prehistorians intuitively guess that there was a cultural exchange between the two types of people. But how cultural exchange took place and who provided new information and innovations to whom remains a matter of conjecture.

Second, we could extrapolate and refer to a somewhat similar Neanderthal practice, namely the use, grinding and mixing of ocher with water, an activity that took place almost 250,000 years ago in Europe, as evidenced by discoveries at the Maastricht site – Belvedere in the Netherlands. Yes, but at the same time, H. sapiens also discovers this technique, completely independently, in Africa.

Now that there is not much difference between grinding and processing fragments of ocher and performing similar actions with plant seeds, and this is obvious. But science is more than speculation or logical exercises. This means evidence, and in its absence, we formulate new hypotheses based on what we have. In this case, we will be tempted to put our money on the Neanderthals. However, since the data is still confused, we prefer to hold off.

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