.

I was just thinking about some book I read where a character had some sort of disease, syphilis maybe. I'm currently reading about the black death; this other book was set in the same time period. Medicine was abominable back then so I'm not quite seeing the innate purpose of sexually transmitted conditions. There's doubtless something I'm missing.

I am talking about caterpillars, maggots, larvae, completely stuck to the ground lifeforms without any flight capability evolving into a completely different, flying lifeform.

It sounds damn near impossible that any lifeform can evolve a trait that reforms their entire body. The change is so drastic and sudden that it doesnt fit into what evolution usually does (small mutations from generation to generation). The entire process requires multiple steps to perfectly work together during the lifetime of a single specimen, to produce a surviving, fully formed adult. If anything is missing, it wont survive.

Mutations cant do all that at once, so what are the steps in evolution towards a successful complete metamorphosis?

And who came first? The caterpillar or butterfly?

I studied evolution a lot in the past years, i understand how it works. However, my understanding raised new questions about evolution, specifically on “why multicellular or complex beings evolved?”Microorganisms are:

• efficient at growing at almost any environment, including extreme ones (psychrophiles/thermophiles)
• they are efficient in taking and metabolizing nutrients or molecules in the environment
• they are also efficient at reproducing at fast rate and transmitting genetic material.

So why would evolution “allow” the transition from simple and energy efficient organisms to more complex ones?

EDIT: i meant to ask it « how would evolution allow this « . I am not implying there is an intent

Is evolution perfect in the sense that if you take microbes and put them onto a fresh world, with the necessities for life,

Will the microbes evolve into plants, and then animals, and then will the created habitat live forever?

Assume the planet is free from extinction events, will the evolved habitat and species continually dance and evolve with itself forever staying in a perfect range of predator and prey life cycle stuff.

Or is it possible for a species to get over powered and destroy that said balance? (Taking humans out the equation which did do this)

I’m not sure when hominids started to develop voices or language but I’m curious to see how much we know about how conversations would go between some Neanderthals and earlier hominids.

I just found out that a pigeon can fly 90Mph now that's just absolutely bonkers I mean I always try not to upset them cause they're some hefty birds but being able to fly that fast is crazy imagine one hitting you on the head that's just wild, does anyone know why they're so fast and how?

What evidence do we have that the hallux (big toe) of A. afarensis is adducted and in-line with the other toes? The actual collected specimens that we have of the foot/hallux (DIK-1-1f and STW-573) appear to be from juveniles, and those specimens clearly display an opposable hallux. So why are we so confident that the toe changes position so dramatically in adults? Is it just based on the Laetoli footprints?

This question came to me while watching the episode of "For all Mankind" where they develop androgynous docking ports for the Apollo-Soyuz joint mission.

There are hermaphroditic animals who fertilize eachother, but this is still achieved through penis-into-vagina intercourse, just with both animals having both genitals.

Have any hermaphroditic animals ever instead of this evolved a sex organ which for example looks like a vulva with petals which can latch onto the petals of another vulva, sperm transfer happens through it both ways, then both animals are capable of giving birth/laying eggs through this orifice?

Has any development of pythigraphy or writing been discovered in other primates living in the wild? Or non-primates

Like an early lineage of small jawless fish that emerged 600 mya and is still small jawless fish? Hope that makes sense.

I've been working on a OneZoom-based tree of extinct species that you can try here: https://www.onezoom.org/extinct/life/

At this point, it is limited to Amniotes to scope the problem space, but we could potentially extend in the future.

Please check out this page which has more details about the project.

It's still quite rough, but I'd love to get some feedback from people!

Cheers.

Title

I was playing A game then I randomly wondered The Title

'Large Head People': Mysterious New Form of Ancient Human Emerges : ScienceAlert

02 December 2024

The brains of these extinct humans, who probably hunted horses in small groups, were much bigger than any other hominin of their time, including our own species.

Paleoanthropologist Xiujie Wu from the Chinese Academy of Sciences (CAS) and anthropologist Christopher Bae from the University of Hawai'i have called this new group the Juluren, meaning "large head people" [...]

In 2023, for instance, scientists found a hominin fossil in Hualongdong, China, unlike any other human fossil on record. It's not a Denisovan, or a Neanderthal, and it does not fit neatly into H. juluensis or H. longi.

China discovers landmark human evolution fossils - SHINE News

2024-12-08 

Discovered in late 1988, the Hualongdong site has yielded remarkable finds during continuous excavations since 2013. Approximately 20 individual ancient human fossils, including a relatively complete skull, over 400 stone artifacts, numerous bone fragments with evidence of artificial cutting and chopping, and more than 80 vertebrate fossils have been unearthed at this site [...]

"They had a 'dining hall' where they cut, chopped and processed food. A karst cave was probably their bedroom for hiding from wild beasts at night, but it has collapsed, and we have not yet excavated it. We hope to discover more fossils in the future," Wu added [...]

A popular theory, based on studies of DNA and fossils mainly from Africa and the Middle East, as well as some human-made products, suggests that modern humans originated in Africa and spread to various parts of the world.

However, in recent decades, discoveries and research of new fossils from various places, especially in China, have shown that this process was actually not simple, but more complex, Xu said.

"The discoveries of human fossils at Hualongdong and related research will enrich our understanding of how this process was completed. Some scholars believe that the origin of modern humans may have been in different places. We will wait and see if the Hualongdong fossils can provide support for this viewpoint," Xu added.

So the common ancestor of mammals is a “rat like creature” that has totally different DNA then a rat, but for all intents and purposes looks the same and fills a similar niche.

Is there a specific name for this? Like how convergent evolution is when two species independently evolve similar aspects.

Additionally, where would horseshoe crabs fall? Ik they’re the “oldest species”. But does that mean they have mostly the same DNA, or they’ve just looked the same for a long time?

Is their viewing distance any better than say the average house cat?

"The fact that rapid brain size increase was clearly a key aspect of human evolution has prompted many studies focusing on this phenomenon, and many suggestions as to the underlying evolutionary patterns and processes. No study to date has however separated out the contributions of change through time within vs. between hominin species while simultaneously incorporating effects of body size. Using a phylogenetic approach never applied before to paleoanthropological data, we show that relative brain size increase across ~7 My of hominin evolution arose from increases within individual species which account for an observed overall increase in relative brain size. Variation among species in brain size after accounting for this effect is associated with body mass differences but not time. In addition, our analysis also reveals that the within-species trend escalated in more recent lineages, implying an overall pattern of accelerating relative brain size increase through time."

--Puschell, T., et al. (2024). Hominin brain size increase has emerged from within-species encephalization. Proceedings of the National Academy of Sciences, 121(49), doi: https://doi.org/10.1073/pnas.2409542121

SciTech Daily article discussing the paper.

What do you think about these findings? Do you know of any other interesting papers looking into hominin encephalization?

Can anyone give me an example of new proteins that have emerged recently?

As opposed to say a close cousin? Even with DNA evidence, couldn’t genetic similarities be due to them having a relatively recent common ancestor?

I joined this sub because it's always an interesting topic, but naturally most of the questions are surface level misunderstandings of evolution; it's not purposeful, it's just the end result of many happy accidents.

But what's high-level in evolutionary theory at the moment? Anything being retracted as outdated or interesting new topics?

I find Shrews fascinating, however I've always wondered why they haven't evolved to last longer without food. It's not that they get hungry after a few hours, they DIE after as little as 5 hours without food.

Is it just that their bodily functions require high energy levels? I feel like they sacrifice some of their speed or other energy draining functions to be better off overall.

is there a kind of feedback loop at the species level that might allow for adaptability of the species,

for example, if you have dark coated mice, and you pick a ton of them and introduce them to a desert-like environment, where sand is golden-brown, a few generations later the mice have coats of color that matches the sand, camouflage

i presume that, in their original habitat where the specific set of traits were advantageous, there was some sort mechanism that enabled the dark coating to be stable, like, narrowing down the probability of possible expressed genes to keep the mice dark coated

but facing a drastically different habitat, like sands, mutability/probability is widened to allow more mutations, like trial and error and elimination, where one combination of mutations might be a happy accident, which then propagates down generations

would sudden change in environment trigger high mutability in the offspring, by some mechanism, maybe chronic stress in individuals causing high mutability in offspring

At first, I have to say that I just started to be interested in evolution and history of Earth and life, just this summer and for now, the most of all I am interested in the species being our direct ancestors i.e. the pre-hominin evolution of humans, starting from the beggining of life. And I still can't get how such complex inventions as viviparty, breathing air and thus switching from living in the water to live on land, switching to nocturnal lifestyle in early mammals and in general becoming a multicellular organism that is one being with self awareness not just a bunch of cells cooperating could occur gradually - like, I understand how in the sense of what happened for this to came to eistence, but how did it happen gradually - I don't get it. I can imagine how we developed organs or even eyes - it is easy to imagine that every few generations a next genetical innovation would cause babies to see better than their parents until we started to see in color just like today. But I really can't get how the things above could happen gradually without the conscious decision - ok, now I'll see what's outside the water, maybe there's better there, or - dinosaurs are too dangerous thorough the daytime, let's just sleep then, maybe we will be safer. I know it is not how it works, but I just can't imagine. The same with the uterus or lungs - like, I know that the develop of placenta was caused by the ancient HIV-like virus infection, but still don't understand how it could happen that the shell completly dissapeared in a process and our ancestor's bodies somehow understood to keep fetus inside them. Same for lungs - what was earlier - an attempt to breath air or lung development? But why would lungs develop without trying to breath air and why would any fish try it if they just suffocate on land? I know that this is a complex question, but anyway I would be grateful for any answers.

Like nature can do it with sharks who live 100+ years. Its not a stupid question but do genes just expire?

Update:

ty for the responses i have read all of them.

still confused

I took an epigenetics course in undergrad and I've been thinking about this a lot since then.

Retrotransposons replicate their genomic sequences by encoding a retrotransposase and insert themselves somewhere else in the genome, where they can make more of themselves and so on. Cells prevent their replication using nuclear proteins that silence their expression, such as methyltransferases. Such enzymes recognize retrotransposons by certain motifs in their nucleotide sequences, which tell them that there is a retrotransposon that needs to be silenced.

I've always wondered this means there is selective pressure for retrotransposons to change DNA sequences for them to be harder to silence. If it is harder for the enzymatic machinery to recognize a retrotransposon, then they will be harder to silence, meaning they can produce more of themselves. I think this is interesting because that would mean the nucleus is a microenvironment where natural selection takes place.

Has anybody done research on this or had a similar idea? I wanted to propose this idea for a research project in graduate school but I don't know how to describe it or who would be interested in studying it.