Dinosaur or Dinosaur Egg?

‘Sixty-five million years ago the dinosaurs had a bad day.’ What if this happens to us, too?

Dinosaurs are big, fascinating creatures that once ruled our planet. They pervaded popular culture, with countless novels, films, and even artworks about dinosaurs produced in the past century. However, if you ask a child toying with dinosaur figurines, ‘Where did dinosaurs come from?’ They’d probably first stare at you blankly, then go on playing with their plastic dinosaurs again. They simply don’t care. You, too, are probably feeling the same way. Believe it or not, learning about dinosaurs’ origins can not only help us understand Earth’s history and evolution, but can also prepare us for future environmental changes and even potential global disasters. (Hopefully, you’ll be able to lecture that ignorant child after reading this article.)

Let’s start from the very beginning. The time is 4.3 billion years ago, just 200 million years after the birth of this blue planet, and there may have already been conditions suitable to support life. Though the oldest known fossils are only 3.7 billion years old, during that 600 million-year window, it’s possible that life may have emerged repeatedly, only to be snuffed out by catastrophic collisions with asteroids and comets. 

Soon after that, the prokaryotic microbes became multicellular organisms, then arthropods, and then jawed fishes. That was 475 to 400 million years ago (Ma) in the Ordovician Period, which was followed by their long transition into the other vertebrates - amphibians, reptiles, birds, and mammals (Tetrapoda) - over the next 100 million years of the famous Devonian Period until 340 Ma. Here, in the Late Carboniferous Period, marked the emergence of the first amniotes, being the earliest group of tetrapod vertebrates to fully adapt to terrestrial life.

The amniotes further colonised land, for they are distinguished by the development of the amniotic egg, which features protective membranes and a shell that prevents desiccation, allowing reproduction away from water, marking another key transition from their amphibian-like ancestors. Next, they diverged into two main lines during the Permian Period: the synapsids and the sauropsids. Synapsids include all mammals and therapsids, which were mammal-like reptiles from which mammals evolved; whereas, sauropsids include reptiles and birds, and can be further divided into anapsids and diapsids. 

Petrolacosaurus kansensis, one of the oldest known reptilian diapsids, is small and looks abstractly similar to a lizard. Together with many of this kind, they evolved into archosauromorphs in 260-252 Ma. Unfortunately, over 70% of all marine and terrestrial species at that time were wiped out in the end-Triassic extinction that spanned across the next 50 million years. 

On the other hand, this global extinction event created opportunities for archosaurs to split into crocodile-like (pseudosuchia) and bird-like (avemetatarsalia) branches. More specifically, the bird-line led to agile dinosauromorphs (~245-240 Ma), including precursors like lagerpetids (hopping forms), marasuchids, and dromomeronids. These had dinosaur-like upright limbs and long legs but lacked full dinosaur skeletal features. Finally, after a 10-15 million-year fossil gap (also known as the ‘ghost lineage’), true dinosaurs appeared unequivocally at 233-230 Ma in southwestern Pangea (South America/Africa), with the most noticeable names being the saurischians and ornithischians like Herrerasaurus and Eoraptor.

Sources:

https://ucmp.berkeley.edu/fosrec/Stucky.html

https://www.nhm.ac.uk/discover/where-did-dinosaurs-come-from.html

https://news.uchicago.edu/explainer/origin-life-earth-explained#when

https://www.britannica.com/animal/reptile/Evolution-and-paleontology

https://www.researchgate.net/publication/6061083_Petrolacosaurus_the_Oldest_Known_Diapsid_Reptile

https://oertx.highered.texas.gov/courseware/lesson/1760/student/?section=5

https://www.geol.umd.edu/~tholtz/H259C/lectures/259Cvertebrates.html

https://www.britannica.com/science/end-Triassic-extinction

Nubulae - where stars originate and die

Nebulae are not only clouds of dust and gas; they’re the place where stars are made and where they’re destroyed. Most people think that space is a complete vacuum, but it’s actually made up of dust and gas particles known as the Interstellar Medium (ISM). About 99% of it is gas and 1% is dust. The gas is composed of approximately 70-90% hydrogen and 10-28% helium, while the remaining 1% is made up of dust, which is composed of heavier elements such as carbon, silicates, and ice. 

The reason we treat space as a vacuum is because the ISM is so incredibly diffuse that it has an average density as low as 1 atom per cubic centimetre. To put it into perspective, Earth’s atmosphere has a density of roughly 30 quintillion molecules per cubic centimetre (3 x 1019/cm3) at sea level. In other words, the gas and dust are spread out so thinly that they’re virtually non-existent, making space behave like a vacuum.

Even if you dismantle all the stars and planets in the universe and spread them evenly across the vast expanse of space, it would still be a near-perfect vacuum, better than any man-made one humans have ever created. 

Yet over millions of years, the ISM coalesces and creates denser regions and clouds called nebulae. It could be because gravity has pulled together gas and dust or because stars have died and their contents are collected into one space.

Nebula Formation
Nebulas can form in several ways, but the most common ones are either from the remnants of dying stars or from their birth. When medium to large stars reach the end of their lives, they explode as a supernova, ejecting heavy elements into space. The debris scatters outwards, forming smaller planetary nebulae, such as the well-known Crab Nebula. 

Larger nebulae—sometimes referred to as ‘stellar nurseries’—form through the gravitational attraction in the ISM. When the gravitational attraction between gases becomes so great, the gases begin to orbit each other more, getting faster as more gas gets pulled in. Eventually, enough mass is gained, and the temperature increases due to its motion so much so that there’s enough energy to induce nuclear fusion, creating a star. However, not all nebulae can do this; planetary nebulae, such as the ones created from star deaths, will slowly disperse as there isn’t enough mass to keep them together.

Nebulae Classifications
Astronomers classify most nebulae as diffuse, meaning they have no well-defined boundaries. This is further divided into emission and reflection nebulae. 

Emission nebulae are named after the fact that they emit their own light, or more specifically, they emit spectral line radiation from ionised gas. These types of nebulae form when the radiation of stars within the nebula energises the gas, so the electrons from the nebula's hydrogen atoms gain enough energy to escape the pull of the nucleus; this process is called ionisation. When the energised electrons eventually recombine with their atoms, they release energy in the form of photons (packets of light). This process gives emission nebulae their glow, often being red or pink due to hydrogen’s spectral signature. 

Unlike the other nebulae whose names give away their traits, planetary nebulae have nothing to do with planets. As mentioned above, planetary nebulae form from the deaths of low to medium-mass stars, about less than 8 times the mass of the sun. 

When a star exhausts its nuclear fusion, it begins to die. Unable to maintain its internal pressure, the star expands into a red giant, while its core shrinks. Its gravity can’t hold the outer layers together, so the outer layers of the star are expelled into space, forming a planetary nebula. The gases form different shapes, such as hourglass, rings, rectangles, etc. Astronomers are still studying how and why these shapes are made.

At the centre of the nebula, the star's core is left to be a white dwarf, a star that’s the size of the Earth but is the mass of the sun, making it one of the densest bodies in space (other than black holes and neutron stars). The white dwarf emits UV radiation, which ionises the gas in the nebula, causing it to glow, similar to how the stars in an emission nebula do the same. 

Nebulae aren't just funny-looking clouds in space, but part of the life cycle of stars themself. From the birth in stellar nurseries to the death in planetary nebulae, it reveals how solar systems form and provides insight into the universe’s composition. Eventually, even our sun will end up as a planetary nebula, rendering everything back to clouds of dust and gas. 

Sources:
https://www.universetoday.com/articles/what-is-a-nebula https://science.nasa.gov/mission/hubble/science/universe-uncovered/hubble-nebulae/ https://www.cfa.harvard.edu/research/topic/planetary-nebulas https://astronomy.swin.edu.au/cosmos/*/Dark+Nebula

Origin of Math Skill

People ask me where my math skills come from. The origin of it. People treat it as though it is a superpower that no one else has. I guess it is true in the sense that it really seems amazing once you manage to do it. However, the source of my mathematics skill is very simple. Here, I will list 3 ways that got me to where I am today, and hopefully, you can get some insights from this article.

#1: Practice, practice, practice!

When I was young, I did math practice nearly every day. I remember I used to get distracted really easily and be really slow. I would take 15 minutes to solve 6 simple addition problems like 27 + 56. It sounds ridiculous, right? But after constantly practicing, I can now not only do 10 of those questions in under a minute, I can do multiplication, and more complex stuff. This probably applies to other subjects. Practice makes perfect, as they say. That has become one of my catch phrases. I would never have gotten where I am, without practicing. Even now, I still go to competitions, do math at home during weekends, and even do IB math past papers when I have time. 

#2: Enjoy it!

For all subjects, this is always true. If you enjoy it, it is very hard to not get better at it. Think of any of your hobbies that you actually enjoy doing. Other than math, I also enjoy playing chess. I am not a grandmaster at chess, but I enjoy playing chess. I don’t play competitively, but still have an elo of 1500. A lot of top-chess players love chess. In order to get better at something, it is a lot easier to do so if you are motivated to do it. Don’t think that you are being forced to do things. “Oh, why do I have to do this?” That mindset itself is the thing that leads to no improvement, which leads to laziness, which turns into a cycle where you get worse and worse. I think, without enjoying chess, I would probably have never reached where I am now, because pushing elo on chess is very tiring and requires not only patience but also resilience. This links to my next point. 

#3: Do it consistently!

As I have already mentioned, I did math practice nearly every day. The consistency of practice was the main thing that led me to where I am now. It is interesting how this is also visible in sports. I remember how in a past FIS newsletter article, in December 2024 when Sarah, a triathlete, mentioned how she “train[s] every morning” “rigorously”. Consistent practice is key to improving. After all, I am not a good basketball player, but when I do play, I make sure I enjoy it. But did I improve? Not really. I would have to practice once a week in order to actually improve. Sarah, on the other hand, “love[s] doing the actual training sessions”. She enjoys what she does, and does it consistently. After all, if you enjoy something, it isn’t too difficult to do regular practice.

In summary, I think what got me to where I am today is small habits and consistent practice, and loving math itself was what allowed me to do everything consistently. Honestly, I think you can do it too. How about you start doing 10 minutes of math practice every day from now on, or if not math, how about a bit of practice on something that you really want to improve in?

Sources:

https://sites.google.com/view/fis-newsletter/issues/december-2024-issue/december-2024-student-spotlight?authuser=0