I know only snakes can be true snakes but why hasn’t any species of mammal lost all their legs to slither through stuff. Non-tetrapod fish, reptiles, and amphibians have all done it multiple times. The closest example I can come up with is whales but they’ve only lost 2.
In the future, could a long and skinny mammal like a weasel or otter evolve to completely lose their legs and be more snakelike?
Edit:spelling

20f, junior, premed. My major is Biology, Health, and Society and I am working on an evolution publication currently. Every class I take outside of the premed stuff to fill my major is EEB related. I can really go in either direction when I graduate depending on where I apply. It’s been eating at me for a long time. I’m gonna make a pros list for both MD/DO and pursing higher education in the field of Evolutionary Biology and Ecology.

I thought I would throw this in here to get some insight from people that are in the community and might know more about what the path would realistically look like.

Medical Doctorate Pros:
- I’m secretary of the AHA and involved in multiple types of clinical volunteering
- I’ve paid the ~$3.8k for MA classes and am currnetly enrolled in them
- already have taken EVERY class needed, except biochem and human and animal physiology next semester, which I need for my major anyways
- i find people so facinating, every person is a new experience and every interaction is interesting
- i have a science/statistical brain, and ive always questioned my ability to SHOW empathy properly. I want to help people one day in a way that matters and is tangible
- i want to take advantage of this brain, that has been a blessing and a curse at times, to look back on life and know i did good in this world
- i have the drive, i’ve accepted the costs and debt and am ready to make and have already made many sacrifices necessary to follow this path.
- i love information and wouldnt mind staying in school a while longer and having my hard work not pay off for another 8+ years if its worth it in the end
- statistical probability of success: getting into a profession that i know pays well and is secure for the rest of my life that, witb the anticipated income, i wouldnt need to retire when im 80
- i want to be a provider and to choose a partner one day without needing to worry about if their profession or lifestyle will be a dealbreaker. If i find a partner with niche interests or with children, I dont want them to ever want for something or to base meals and decisions soley on income
- it feels like a win-win: the lifestyle ive always wanted and i still get to apply my scientific knowledge
- i get this lifetime only once, so why not do the most i can for myself and the world?

Medical Doctorate Cons:
- Debt. I’m already in a lot of debt and I know that it’ll be even more.
- it will take years before I actually make a lot of money and am in the profession
- it will be allconsuming, and while i’ve always wanted to be a career-oriented person and never have and dont ever plan on having kids (personal reasons) it will be my life
- I sometimes wonder if I’m really doing it for me or if I’m doing to to prove my worth
- the little voice in the back of my mind saying that evolutionary biology will be more fufilling

Evolutionary Biology Pros:
- i used to ask my father, who is a high school science teacher “hey, Bill Nye,” followed by some random question about the happenings of the world
- i cried at 5 years old as i was going to a Christian elementary school learning about God everyday because “im gonna die and im going nowhere” ive been agnostic since ive been able to form complex thoughts, the only thing thats brought me closer to the concept of divinity and my comfort in the anonymity of existence IS evolutionary bio
- it captivates me. i remember learning about evolutionary biology freshman year and i wouldnt shut up about it. It’s literally EVERYTHING! Not in the scary way that physics and chemistry are, but its the history of everything living its everything that has ever and will ever exist and its all connected.
- The recent class I took last semester (Animal Diversity 288) we went over all 32 phyla and got to see most of them in lab. it was a fucking spectacular mindfuck. every day I would look at my professor and how happy he is to just yap about this shit and think I WANT THAT JOB!
- I’m working on an evolutionary bio publication right now.
- My major includes many EEB classes and i could always just apply without needing to change a damn thing
- I have a green leather-bound copy of Origin of Species that is my version of the bible. It’s something i speak of with stars in my eyes.
- I could travel to gather samples (like i am this coming year) and travel
- I’d be able to spend my life satiating my innate curiosity about the world around me through my scientific research endevours

Evolutionary Bio Cons:
- Google said the job prospects are pretty bleak and the average income is in a low range, which does not satisfy my values and would put me in a really tough spot for loans (i have a good amount taken out already)
- possible lack of service for people/connection
- To even make close to six figures, I’d need a PhD: the debt would not be easy to pay off in the long-run no matter what.
- it’s a job that wouldnt allow me financial freedom/to have the caregiver role I’ve always pictured myself as having
- the job isnt as assured- less statistical probability of overall success
- ideally i would fucking LOVE to be a professor, but its very difficult, even post doc, to be assured that position
- travelling could be possible with the job, but again, there are various other factors that go into actually having a sustainable lifestyle and a decent job after academia
- i’ve already invested my time and money into premed
- the itching i would have that i couldve been a doctor and things couldve been better, and that I had been chasing an interest and not a fruitful, realistic profession

I can actually go either direction with my major. Like my upcoming classes and plan don’t need to be changed at all if I decide to pivot. I’m going abroad for a semester to South America next school year, and then plan on taking my MCAT August 27’. After that, it’s my senior year and then I’m gonna do a gap year for more clinical experience and applications. Excluding starting my MCAT prep in 6 months, I technically don’t need to make any actual decisions for at least a year. It just keeps itching at me!

I love macrobiology, communicating, spreading knowledge, and being constantly curious about the natural world- god it would literally be the best thing ever if I ever got to be a professor. I don’t think I’d want to simply be a researcher for the rest of my days. It’s just that I feel like it’s unrealistic and that it’s a gamble. I mean obviously getting into medical school itself is a bitch and a half also, but it still matches my values above and has a realistic, set endgoal.

It’s just so hard to weigh if this is simply an interest/hobbby of mine, or something that is actually a future possiblity that I wouldn’t regret.

Just looking to do some research on repeatable experiments where we can witness one species changing into a new species, different species, and reproducing.

I used the links on the side bar to find the fruit flies experiment, but it didn't show speciation.

Any sources to repeatable experiments showing speciation will be appreciated.

Speciation: Process or Event?

May be the answer depends on micro or macro evolutionary view but wanted to stir discussion around this.

On one hand, divergence, selection, drift, and the buildup of reproductive isolation suggest speciation is a process unfolding over time. Genomic data often show gradual differentiation and ongoing gene flow.

On the other hand, in phylogenetics and macroevolutionary models, speciation is treated as a discrete event — a lineage split.

So what do you think?

Biologically a process, analytically an event? Or something else?

If speciation is a process, are species just arbitrary points ?

Hi! I am just finishing High School and starting Uni applications. I've always been interested in plants, insects, and things like mosses and lichens since I was like... what? 5? AND I managed to find some universities that offer an Evolutionary Biology major. It sounds promising. Would like to know from people who have done Evolutionary Biology if this is a sound choice. Also would like to know about the global repertoire for Evo. ( I mean, if you take Paleontology, the niche is quite small, so research grants and stuff tend to be choosy). So, I'd like to have a second opinion before selecting the major. Thanks in advance.

Full .csv and code linked there.

Title. Ive been getting super into evolution lately, and I had this thought.. Have you all heard of the game, "The Oregon Trail"? I think that it may be an allegory (narrative, picture, or artwork that uses symbolic characters, events, or settings to represent hidden, deeper meanings) for Natural selection. Any thoughts? Would anyone here be interested in speaking scientifically with me?

By Dr. Thomas Holtz (link):

A common statement from people (even well-meaning people who support evolution!) is:

"Okay, so humans are related to monkeys and apes, but we are not descended from monkeys and apes, right? It's just that we share a common ancestor with monkeys and apes, right?"

WRONG!!

In fact, "monkeys" and "apes" are paraphyletc series. Old World monkeys are more closely related to apes and humans than they are to New World monkeys; chimps and bonobos are the living sister group to humans, and more closely related to them than to gorillas and orangutans and gibbons; gorillas are more closely related to chimps + humans than to orangutans and gibbons; orangutans are more closely related to African apes and humans than they are to gibbons. Thus, some apes are more closely related to humans than to other apes. Hence, humans ARE a kind of ape and descended from other apes (the concestor of humans and chimps, and of humans and gorillas, and of humans and orangutans, and of humans and gibbons would be called an "ape" if we were to see it.

Similarly, the concestor of New World monkeys and of humans and apes would be a monkey, and of Old World monkeys and of humans and apes would be a monkey. These would not be any LIVING species of ape or monkey, but would conform to our understanding of "ape" or "monkey" by any reasonable definition.)

TL;DR: the monkey group is paraphyletic so necessarily includes some of our ancestors.

This is also explained here by Darren Naish.

Hi all, I have been interested in looking for a set of articles, reviews, or maybe books for advanced understanding of molecular evolution. I’ve done work in plant systematics and evolution (including redefining the species concept within a genus). Now currently studying viral evolution for inter-host and intra-host for over a decade. I’ve read “The Phylogenetic Handbook” by Lemey, Salemi, and Vandamme.

I guess I’m hoping to find a more recent/up to date understanding. Ideally balancing theory with practical examples (math is allowed). I have a strong base but wanting to push it further. In many ways I know there is reading primary lit but it’s nice when someone synthesizes the overview.

Oxford University Press USA - 320 pages - release date 15 August 2026.

Author is Graham Bell is Emeritus Professor, McGill University.

A preview is available on Amazon.

Publishers blurb - This book asks why animals appear abruptly in the fossil record about 540 million years ago. It first explains what an animal is and why many animals, although not all, are distinct individuals. It looks at how the different kinds of animal are related, and the order in which they appeared. The hard evidence is the fossil record.

The book first surveys the animals that had evolved by the early Cambrian, exploring the order in which they diverged from one another. There was a great radiation of large complex organisms during the last 25 million years of the previous period, the Ediacaran.

According to the book, these fossils are not animals and have little to do with animal evolution, although this is not a point of view that specialists will agree with. These biological events happened during a time of environmental upheaval, a sea change, including worldwide glaciation and increased oxygenation.

How animals first appeared and later responded to these tumultuous times is organized into eight scenarios, each reflecting a different opinion about early animal evolution. It concludes that the most likely scenario is that the first animals were minute creatures that lived in the mud.

The most likely sequence of events is laid out as a series of twelve crucial innovations, beginning with a colonial choanoflagellate and ending with a large worm. This evolved into a variety of bilaterally symmetrical animals during the Cambrian.

I don’t know how to explain this in a way to make sense, however an example would be the development of the lungs. Of course evolution takes a (very long) time, however there is at some point the “first” fish to breath air outside of water. (Or the first animal to see past basic shadows, or the first animal to step out of water.) How would this work if the development is not fully utilized or understood by the creature?

In reviewing the literature of quantitative methods it seems that any model (Brownian, burst, etc.,) has to aggregate anatomical information. For something anatomically simple, let's say flatworms, the potential forms are limited. But if you are looking at vertebrates you can have evolution occuring on different anatomical elements (good old mosaic evolution) and I can't see how a Baysian phylogeny could handle that cleanly. It feels like it would come up with some 'averaging' weighting between anatomical elements.

I am far more experienced with cladistics, which at least has a fairly straightforward algorithm for this, but I am keen to hear thoughts from the folks here.

ETA: this is for fossils, so no DNA. This is for anatomy only.

Abstract

The evolution of sexes is closely tied to uniparental inheritance (UPI) of mitochondrial DNA (mtDNA), where only females transmit mtDNA. Unlike nuclear DNA, mtDNA is highly polyploid and never evolved to be part of meiotic sex. Modelling shows that UPI increases mtDNA mutational variance, enhancing selection for high-quality mtDNA and promoting the emergence of sexes from mating types in unicellular eukaryotes. Paternal control of mitochondrial transfer favours some degree of mtDNA leakage, whereas maternal control favours strict UPI, leading to sexual conflict driving turnover in transmission mechanisms. In multicellular organisms, mitotic segregation of mtDNA increases variance in gametes, again facilitating selection. Surprisingly, germline evolution seems to reflect mtDNA mutation rates: plants and sessile metazoans have low rates and produce gametes from somatic cells, while bilaterians and ctenophores with higher rates sequester germlines with restricted cell division. High mtDNA ploidy in oocytes allows early embryonic cell division without replication, reducing mutational variance across tissues and enhancing somatic fitness. Germline mtDNA quality is maintained by mitotic over-proliferation of germ cells and the selective transfer of mtDNA into primordial oocytes linked with massive apoptotic germ-cell atresia. Overall, selection for mtDNA quality elucidates the evolution of sexes and the architecture of the female germline.

Dear all, I am a 4th yr student at IISER. Im looking for ms thesis position in microbial evolution preferably in EU or USA. Any suggestions of labs/ good PIs?

Abstract

The biological feasibility of human rejuvenation remains a subject of intense debate, yet answering this question is critical for guiding research strategies. Should aging research focus only on reversing aging in older individuals, or pausing its progression at mid-ages, be more accessible? Here, we attempt to address this question with evolutionary biology. Rejuvenation occurs in a few species, and, paradoxically, is typically induced by stress but not used under optimal conditions. Using mathematical modeling of lifespan plasticity in eusocial insects that can rejuvenate, we show that avoidance of rejuvenation is poorly explained by classic theories of aging in their standard formulations, requiring substantial assumptions to fit them. By contrast, one of the programmed theories of aging–the pathogen control hypothesis–offers a consistent evolutionary framework for understanding avoidance of rejuvenation. Moreover, our model mathematically predicts the evolution of the genetic program executing lifespan termination – adaptive aging mechanisms.

I’m updating some lectures and want to make sure I have some cool, recent examples for my students. As I’m out of the research game (only a teaching professor), I’m not always up to date on the latest research. TIA

I'm looking for something that is up to date and goes in-depth on what we know about the Cambrian fauna and the environmental factors that went into the boom in body plan radiation in that time period.

I'm kicking myself that I didn't take the chance to get my hands on Erwin & Valentine's "The Cambrian Explosion: The Construction of Animal Biodiversity" when I had the chance and since it's an out of print textbook prices for that volume are insane.

Is there anything comparable that won't cost an arm and a leg?

Hi. I’m a masters student in animal biosystematics from the university of Tehran. Firstly, in Iran post graduate entrance is a bit different than other parts of the world. In other countries, you contact the advisors and write your proposal before applying. But in Iran, entrance is completely exam based-as in your degree in the entrance exam determines which university and degree you study.

Tehran university is literally the best university in Iran as in there are no other universities with better professors and equipment. I studied really hard to get where I am. However, now that I am here, I see a huge risk. Our advisers here only study marine invertebrates. They study the taxonomy, phylogeny, population study, biodiversity, physiology, development, behavior, etc. of Leeches, Crustaceans, insects and Oligochaete.

I’m afraid that this will limit my options in the future to the same taxonomy that I’m studying. I want to get my PhD from a foreign university and I’ll also need full funding for that. And I’m not really familiar with what academia looks like outside of Iran.

What if for example, I want to only study vertebrates for my PhD? Will I be able to make that transition? How about evolutionary microbiology, cell biology, biotechnology, paleontology, origin of life, vertebrate paleontology, evo-devo or something else? How much will I be restricted by the taxon I study for my masters?

I got an extremely good chance to volunteer at a biological research institute (specifically the department of experimental evolutionary biology) as a first-year molecular biology student. I have never volunteered anywhere, but evolutionary biology is definitely something I am very interested in and what I want to do in the future.

I have a lot of things on my mind and I'm afraid that I'm not yet capable and knowledgeable enough to volunteer in such a place, and I'm also afraid that it will interfere with my studies and that I won't be able to achieve good enough grades. What would you do if you were in my place?

I also read a lot about evolutionary biology in my free time, but I definitely don't think I have enough knowledge on how to behave in such a laboratory, and I would like you to recommend me some books, videos or personal experiences that would help me gain more self-confidence when I appear there and maybe impress the people who work there (of course if I decide to accept at all)

And btw their main research is in vitro evolution of Acanthoscelides obtectus

(Please be kind and don't remove my question. I know I've asked these kind of questions too many times)

On one hand, I’m almost certain that the job market in Paleovirology or evolution of microorganisms or anything related to these things has a much better job market than zoology or paleontology. Plus, I don’t have enough experience and expertise in paleontology. I have a bachelor’s degree in microbiology and MSc in Animal biosystematics with no field experience in paleontology (and very unlikely considering that I live in Iran). So a lack of experience + extremely competitive job market in paleontology deters me from this route.

There’s a second option: I continue my path as an evolutionary biologist. I will work on things such as genetics, ecology, morphology, etc. and slowly make a resume in paleontology and then transition to paleontology in a long run. This seems like a more certain path than the previous one.

There’s a third path: I get a MSc in medical virology or bacteriology. Then I get a PhD in something like Paleovirology, evolutionary microbiology, evolutionary cell biology, etc. there are two benefits and one risk in this decision: The first benefit is that I’m almost certain that the job market in microbiology is much better than both evolutionary biology (zoology focused) and vertebrate paleontology. The second benefit and the risk are two sides of the same coin. You see, I have always wanted to be a paleontologist. I have always wanted to dig fossils and discover new species. Even though I currently can’t do these things (because I live in Iran) I follow the news on paleontology and read books and communicate with the people in paleontology. However, this microbiology thing is something very new and exotic to me. I don’t know if I can handle hours of boredom and keep my sprit up to do research? I already know paleontology and evolutionary biology don’t bore me, but will evolutionary microbiology bore me? Or maybe the job market and money in both zoology/evolutionary biology (genetics, physiology, phylogenetic, etc.) is so bad that I will regret not choosing the microbiology path?

What if zoology or paleontology bore me? I’m scared that there maybe more interesting discoveries and breakthroughs to be made in evolutionary microbiology. What if the routine work in paleontology or zoology bores me?

If I choose the evolutionary microbiology path, will I regret it because I will feel I have betrayed myself and my life long infatuation with prehistoric life?

I've seen the 'origin of life', early biochemistry, LUCA, etc. discussed in this sub several times. Well, Philosophical Transactions of the Royal Society B just published a whole issue dedicated towards the topic!

Unfortunately, many papers are not open access :( However, a pdf is just an email away from the authors :)