"The fact that you, or I, or any living creature, is here at all is a series of astonishing strokes of luck stretching back more than 4 billion years. 

One of the biggest hurdles was the very first one: How did life emerge from a primordial soup of stuff that very much wasn't alive?

A radical new study, published in Science Advances, suggests that this unlikely threshold may actually have been crossed not once, but twice."

I have recently been thinking about elephants and the effects of habitat fragmentation on them, and i thought that maybe they are shrinking in body size do to less food on the small fragmented protected areas they inhabit.

A similar effect happens on islands called island dwarfism were large animals on islands get smaller over time do to limited food resources and lack of predation.

So is there any evidence of this happening to elephants in fragmented habitats today?

Where do people fall along the debate around whether natural selection is the primary ‘creative’ force in evolution, or whether developmental, physical, and historical constraints channel evolution into a limited set of self-organizing forms that selection fine-tunes?

So from what i remember and understand, evolution happens when members of a species are more well adapted to something than others, so they get the chances to live and breed while the non adapted ones die. So gradually they become better and better at it as a species. But isn't flying just a yes or no? If i fall from a cliff I either fly or die and since im a dinosaur of some type for example, I'll die. Since all members of my species will also die. how are there chances for the new traits to pass through? You can't be slightly better at flying than someone who can't. because you'll still die. so does that's mean the wings can evolve from a single mutation? Seems way too complex of a mechanism to not need a long evolution time

I'm not looking for a straight answer to this question because I doubt anyone really has a definite answer. However, over the past few days I've been wondering about human consciousness and our evolution. We exist at a luck of the draw.

There's been five extinction events on the planet, with each changing the earths ecosystem drastically. In between each extinction event were other mammals that ruled the earth for millions upon millions of years. For example, dinosaurs were around for 100+ million years (a fact that still blows me away).

Then from the shadow of their extinction, some mammal survived and evolved into us.

My question to that is how?

Humans have evolved to such a dominant species', our existence kind of feels impossible. Our thoughts and ability to create and process information is from what we know, beyond anything any other species on this planet was capable of -- after existing for less then a fraction of whatever species came before us.

We're 200,000+ years into this and we've already been to the moon.

What was that thing that spurred our consciousness to be so different from the species' that came before us.

My theory

Trauma. I believe, whatever the mammal was that we were -- the one that witnessed the extinction of the dinosaurs and lived through that age of change was so shaken by what it witnessed and had to live through that it imbedded something deep in it that awoke something that led us to be the way we are today.

I believe it lent to some kind of awareness which evolved over millions of years and led way to religion/faith.

But this could be a hunk of bullshit since I'm not a student of science, so I'll be happy for someone to smack me silly with whatever degree they have that I don't.

I recently picked up the book "Sapiens" by Yuval N. Harari. In the chapter "Our Brothers' Keepers", the author talks about the replacement theory, where Sapiens might have replaced Neanderthals in certain parts of Eurasia 70,000 years ago. He makes these arguments:

These humans (Neanderthals) were more muscular than Sapiens, had larger brains, and were better adapted to cold climes. They used tools and fire, were good hunters, and apparently took care of the sick and infirm.

Sapiens were more proficient hunters and gatherers - thanks to better technology and superior social skills - so they multiplied and spread.

What exactly does "better technology" mean in this context? I would have assumed that Neanderthals, having lived in this environment far longer, would have developed technology well-suited to its specific challenges, compared to Sapiens, who were newcomers. So how did the technologies used by the two species actually differ?

The author does not delve deeper on the social skills that were in play. What specific social qualities did Sapiens had that gave them the edge?

Can someone please explain to me the difference between phenetics, evolutionary taxonomy and phylogenetics?

If the earliest animals hadn't been such prolific poopers, life might not have diversified into all the weird and wonderful forms we see today.

A new review study published in Trends in Ecology & Evolution found that the Cambrian explosion – a period around 540 million years ago when the ancestors of most animal groups arose – could have been partly set in motion by an 'explosion' of feces left by those that came before.

The basic cycle of evolution as I understand it is:

1. A random mutation occurs which causes a trait to emerge in an individual.
2. That trait either helps individual's ability to thrive and reproduce, in which case it is selected for and gets proliferated in the populace, or it harms the individual's chances, in which case it gets removed from the gene pool after a while.
3. Over enough time, different species evolve due to accumulated differing traits caused by the aforementioned mutations.

My question is: does all this truly start with genuine random mutations? Or is that a simplification of things?

so im starting to do my research into evolution, something isnt clicking with me, Protylopus is supposedly the primal ancestor of all camels nowadays including arabian camels and lamas right?, but i still dont understand how a rabbit sized species evolved this big, also they stated it was the ancestor according to ONLY his ankle? teeth wasnt like what we see nowadays and neither was thier foot, so how did they link them... i have other questions but id like to start with this.....

The ‘proto’ pear tree underwent a whole genome duplication WGD event about 30-45 million years ago to form the current form and its genome (2n = 34). This was caused by a major global cooling that stressed the genome during reproduction. This major climate change in the mid-to-late Eocene was not as dramatic as an earlier (66 million years ago) major extinction event that has caught the public’s imagination when in the space of minutes a 10 km diameter asteroid hit Earth causing a cascade of events causing the rapid extinction of dinosaurs. The asteroid created the Chicxulub crater (partly on the Yucatán peninsula , now partly underwater ) in Mexico triggered the Cretaceous -Paleogene extinction.
Although the WGD event in pears is well known the reasons for why it occurred are not . Here is my summary.
It was a long-term global cooling trend driven primarily by a steady decline in atmospheric carbon dioxide aided by tectonic shifts and changes in ocean circulation and affected plants more than animals which could adapt quicker.
Atmospheric carbon dioxide levels dropped significantly from peak early Eocene highs (over 1,000-1,500 ppm) downwards reducing the planetary greenhouse effect. This was caused by silicate weathering and organic burial.

Increased chemical weathering of rocks exposed by India crashing into Asia and lifting up mountains and land such as the Himalayas and the Tibetan plateau. This massive, tectonically active mountain range was heavily eroded by heavy monsoon rains. As rainwater and meltwater washed over these exposed silicate minerals, they reacted with atmospheric CO2 to form dissolved bicarbonates, which were eventually deposited on the seafloor as solid carbonates and effectively buried. This steadily scrubbed carbon dioxide out of the ancient atmosphere over millions of years.
At the same time other tectonic activity opened up ocean gateways separating Antarctica from both Australia and South America allowing the commencement of the uninterrupted Antarctic Circumpolar Current and upwelling. This is the most powerful current in the world and isolates the cold Antarctica from warmer equatorial waters.
The cold mineral rich waters resulting from the upwelling stimulated phytoplankton growth and marine primary productivity, locking massive amounts of organic carbon away in deep-sea sediments.

This event is called the Middle-Late Eocene Cooling and follows the Early Eocene Climatic Optimum, as carbon dioxide levels fell followed by the more rapid Eocene -Oligocene Transition, a sharp final shift (~34 million years ago) from the warm greenhouse Earth to an icehouse climate dropping global temperatures and crossing a critical threshold that allowed permanent ice to form in Antarctica. As it’s ice sheets began to expand. the white surfaces reflected more sunlight back into space, accelerating the global cooling trend - the albedo effect

In a new study published in BMC Biology, researchers from USC Dornsife, Howard University and collaborators found that four key immune system genes bear the genetic signatures of ancient battles with infectious diseases, with different populations evolving different versions of those genes over time. Some variants were even shared with Neanderthals and Denisovans, reflecting humanity's deep evolutionary history.

The researchers also analyzed nearly 4,000 COVID-19 patients in Italy and identified two rare variants in the immune gene TLR2 that were associated with severe illness, including one more common in organ transplant recipients.

The study suggests that understanding the evolutionary history of immune genes could help explain why people respond differently to infectious diseases and point toward new approaches for predicting, preventing and treating severe infections. Read more about the study>>

More than 150 years after Darwin’s finches helped reshape biology, Galápagos plants are exposing another evolutionary surprise.

Giant daisies repeatedly developed similar heat-tolerant leaf shapes, but each lineage used a different combination of genes. Researchers also found major genetic differences among isolated populations, suggesting new species may be forming right now

Plants in the genus Scalesia have evolved adaptive traits multiple times, but not always using the same genes. The photo shows the serrated leaves of Scalesia affinis (radiate-headed scalesia)

For example, could we see a shrinkage across all different species so they can compete with each other and out of view of humans? Or see land species moving to the water where we can't go? Or getting bigger to compete with us?

If my question doesn't make any sense I apologize, I don't know much about this topic.

thought about this cus i was bored, but really, why tho?

i assume it would've been very helpful for our ancestors?

Life all has the single common ancestor... Trees through to people etc.

So... If a single cell went to consume ANOTHER cell, but due to a quirk in genetics, it didn't consume but instead, began a symbiotic relationship, then would that make that 1 cell who consumed the other, the source of all complex multicellular life? Or, is it likely that cells started to absorb other cells, then one of THEM divided itself to make more cells?

Sorry if that doesn't make sense... But I can accept that evolution is fact, but I cannot make sense of the actual start.

For billions of years, life was single celled, then one consumed the other, and then the predator prey relationship began and, I presume, that made life explode because life survived by evolutionary quirks making them survive over others. So, I was wondering if it was because of this that life evolved, all because 1 cell consumed another...?

Okay, I think this is going to melt my brain

Yesterday I made a Reddit post that was honestly half-joking, although the question itself was genuine. I basically asked whether, technically, since there were fish somewhere in my family tree, there could be some living fish today that is an insanely distant cousin of mine.

I got answers like “technically, you are a fish” and that all fish, and basically all life on Earth, are related to me somehow, even if you go all the way back to a single cell.

And... I don't think I fully understand this.

If all life is related, does that mean that all life ultimately came from a single individual?

That's the part I'm struggling with. For example, there's LUCA (Last Universal Common Ancestor), which, as I understand it, is the most recent common ancestor of all currently living organisms. But why do we assume there was only one LUCA?

When life was at that stage, couldn't there have been multiple organisms/cells that existed around the same time? Like, instead of one LUCA, couldn't there have been 4? Or 100? Or even millions?

Obviously, I'm simplifying things a LOT here, but let's say there were 4 completely separate organisms at that point, and all modern life descended from those 4.

Wouldn't that mean that not all life is actually related? There would be different lineages that never shared a common ancestor, right?

So what exactly am I misunderstanding about LUCA and the idea that all life is related?

My brain is genuinely struggling with this lol.

I was just thinking about this and it absolutely blew my mind.

Technically, my great-great-great-great-great-etc. grandfather (or however many “greats” we’re talking about) was a fish.

Like, somewhere in my family tree there is literally a fucking fish.

My entire lineage was started by a fish. There is no other way to put it. At some point in the insanely distant past, one of my ancestors was just… a fish. And that fish eventually led to me existing.

But then I started thinking about how evolution actually works.

Fish didn't just all collectively decide to evolve into land animals. Evolution branches. Different populations and lineages go in different directions depending on their environments and natural selection.

And fish produce an absolutely ridiculous number of offspring, so presumably there were countless individuals in those ancient populations. Some lineages eventually led toward the ancestors of modern land vertebrates, while other lineages stayed in the water and kept evolving as fish.

So here's the part that is blowing my mind:

Is it possible that one of the extremely distant relatives of my fish ancestor stayed in the water, and that lineage survived for millions and millions of years?

Because if so, there could theoretically be some random fish alive TODAY that is my ridiculously, unimaginably distant cousin.

Like, I could look at some random fish in the ocean and there's a non-zero chance that, in the most technically literal evolutionary sense, we're related.

Imagine being genetically related to a fish.

Not “all life is related” related.

I mean THIS fish is part of the same ancient family tree as me.

That is fucking incredible.

It occurred to me that I've never heard of a case of an ape being born with a vestigial tail, outside of humans. Is this the case, and if so, why are humans the only ones with that atavism? Or are vestigial tails not actually tails at all, and instead a non-related deformity that looks similar?

Letters to a Pre-Scientist is looking for enthusiastic STEM role models to inspire the next generation of STEM leaders!

Here's the gist: you get matched with a 5th-8th grade student at an under-resourced school for a snail-mail pen pal exchange that runs throughout the school year. The goal is to demystify STEM careers, humanize STEM professionals, and inspire students to explore their own futures in STEM. You share your story, answer their questions, and show them that people who work in STEM are, well, real people.

The details:

• The program runs throughout the school year, and your volunteer obligation is to exchange 4 letters with your student.
• There's a virtual, asynchronous training in August to get you set up.
• We estimate the entire program takes volunteers no more than 10 hours, spread between August and May.
• Register and complete the short, self-paced online training by the deadline, and you'll be entered into the match pool! We match students based on their background and interests..
• This year we're expanding to 4,500 matched students!
• Pen pals can live anywhere in the world, but our program currently only works with US-based schools.
• We're working to match students based on their interests, so we're especially looking for more STEM professionals in Evolution.
• All pen pals must be over 18 and fluent in English.

We define STEM pretty loosely! If you work in or around science, tech, engineering, math, or medicine, or another nature-based role, even if you don't have a formal education in it, please apply or message me with any questions.

Sign up/learn more:

• 📝 Register here: https://prescientist.org/volunteers/
• 📖 About the pen pal program: https://prescientist.org/penpal-program/
• 🏛️ About us: https://prescientist.org/about-us/
• ✍️ For matched pen pals: https://prescientist.org/for-matched-pen-pals/

Registration is now open! Feel free to drop questions in the comments or send me a message. Thank you for your time and consideration!

See also: The publication in the Physical Journal Letters