Derniers billets

A double edged sunscreen

Photograph of the surface of an arid soil. On the right, the soil is partially covered with young biological crusts whereas on the left the crusts have reached maturity and taken a dark colour. (Credit: Ferran Garcia-Pichel)

 

Biological soil crusts are unique ecosystems in arid landscapes (whether cold or hot ones) or can be colonisers of habitats disturbed by climatic catastrophes or humans. Recently, a team of scientists examined the capacity of a type of biological crust to produce a kind of sunblock but it seems that this molecule comes with its own harmful costs… (more…)

Terrorists – could they just be nuts?

illustration of are terrorists nuts
At Sci&Fi, we seldom comment on current affairs, mostly because it is not our place to do so. However, sometimes research can enlighten and inform wider, and often political, debates. In a recent article, two psychiatrists asked: is it possible that the terrorists, notably from ISIS (a.k.a Daech), are just pathologically ill people? And we felt that a more psychiatric examination of terrorist actions and behaviours, would bring some light into debates that have been raging over social media.

They broadly classify terrorists in two categories: (more…)

A 3.4 billion-year-old snapshot – Fossil Friday

There are amazing things to learn in the world of palaentology and archaeology and then there is this. Things that just blow it off. Indeed, in this week’s Fossil Friday we’ll be discussing about a 3.4 billion-year-old fossil. One that dates back to the times when Life appeared on Earth. And we’re not talking about some old finding, no, no, we’re talking about a discovery that was published this week.

photograph of fossil microbial mat

Photograph of the facies of the studied rock formation. On the close up on the right, thin sheets (laminations) can be observered (taken from Duda et al.).

These precise fossils are called stromatoliths, (more…)

The newest addition to our family – Fossil Friday

It is quite rare that we can add a new member to the Homo family, but it is what happened last year. Homo naledi, a long lost cousin of our species, has been added to the already complex family tree of the genus Homo. At Sci&Fi, we just wished these other humans were still alive, it would be such a fantastic world to have a mirror of our own humanity in modern times. Who knows how History would have unfolded? But let us not go off topic…

Homo naledi, assemblage of skeletal remains (taken from Berget et al.)

More than 15 000 bone pieces of, at least, 15 individuals, (more…)

Happy New Year 2016

Hey everybody,

we hope you all enjoyed the festive season fully. In 2016, Sci&Fi is coming back to bring you your dose of Science in various formats. Sci&Fi is still young and is an experimental ground, hence it is possible that various new contents appear or older ones disappear. Whatever it may be, Sci&Fi needs your support and your comments so do not hesitate to join us on Facebook, on Twitter or to leave a comment on the site !

Let’s explore the past, interrogate the present and dream the future on Sci&Fi!

Adrien and Hand for Sci&Fi, over and out.

Ancestral hair – Fossil Friday

Fossil of Spinolestes

Fossil remain of the Spinolestes xenarthrosus

Here is the Spinolestes xenarthrosus, or the fur ball as it has been nicknamed by the media. But it does not do it justice because this early mammal is the oldest evidence for a lot of features. While it is hard to appreciate it in this photo, it contained one of the basic elements that constitute modern mammals, hairs. Indeed, its skin and fur closely resembles modern mammals, nothing out of the extraordinary if it wasn’t for the fact that is 125 Millions of years!
There are a couple details that are interesting here about his animal. (more…)

Unnoticeable cooperation – Fossil Friday

There are discoveries that await to be made. In 2012, an astonishing discovery was made on a 453 to 458 Million years old slab of rock that had been sitting in a museum for already over a century. It was discovered that a colony of a species of prehistoric plankton was full of connections between the individual living spaces.  A feature that is either unique to this species or has also gone unnoticed in other sister species.
Graptolite specimen - Dicranograptus aff. ramosus

What you see is an example of graptolites. It is a word of greek origin meaning “written rock”. Graptolites are a class of extinct marine animals (a kind of plankton actually). They have the particularity of living in colonies and of building their own dwelling structure/housing complex which is called a rhabdosome, this is the part that is circled on the picture above. Rhabdosomes are mostly what is left of graptolites since their soft bodies do not fossilize well. Rhabdosomes contain hundreds of individual tubes/personal houses called thecae.

Rhabdosome are actually what have been used to tell different species apart. Indeed, they can be very varied from a single tube to complex branching or patterned structures depending on the species. Equally, depending on the species the rhabdosomes could have been attached to the ocean floor, free floating or attachable to sea weed etc.

The species here is thought to be Dicranograptus ramosus and there was an additional feature that had been overlooked for the century the slab of rock had been exposed. It was found that there were connections between the theca. It turns out that there actually are two types of connections and that they vary across  the colony. There are these ‘Hourglass’ and ‘Strap-like’ connections.
Graptolite colony with emphasis on network connecting theca

The image above emphasises the contours of these connections. They might be indicative that different type of individuals were inhabiting the colony and therefore that there might have been a division of labour within it. The thecae being all the same, it is thought to not represent sexual differences (dimorphism).

Could you imagine how many more discoveries are waiting to be made on fossils neatly put away on shelves or even exposed to the public?
Adrien for Sci&Fi, over and out.

References:
Zalasiewicz, J.A. et al. (2013) Polymorphic organization in a planktonic graptoloid (Hemichordata: Pterobranchia) colony of Late Ordovician age. Geological magazine. (PDF)
Encyclopedia.com, Graptolithina.
Eurekalet. 2012. Prehistoric builders reveal trade secrets.

Visual credits:
Graptolite Specimen, Paul Witney, BGS, (c) NERC 2012
Rhabdopleura compacta, Dr. Atsuko Sato, University of Oxford.

Nutella, good or evil – examining the controversy

Controversy Nutella - en - short
You may have never heard the controversy around Nutella that raged earlier in 2015. Everybody got emotional, the Italian officials were offended (Ferrero the company that makes Nutella is an Italian pride) and it ended up being a battle between who will never let go Nutella and advocates from various  horizons. At Sci&Fi we shook our head in dismay – is anyone, ever, able to keep their critical minds? So, here’s a little information that gives you an overview of the pros and cons that should have been at the centre of the debate. (more…)

Fuuusion

And that is it, both versions of Sci&Fi on a single website!

You may have noticed it as well, all the dates of the posts prior to this one are all the same, that is because we have moved servers! We have fused all of our content on this single website which is now available in French and English!

We hope you will like it, do not hesitate to leave a comment or to join us on Facebook or twitter @Sci_and_Fi.
Let’s explore the past, interrogate the present and dream the future on Sci&Fi!
Adrien and Hans

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