Ask a Biologist

[Mark1031]

(-> no idea how to interpret the question; field of work? Or is anything else meant?)

Nothing implied. Just what are you looking for- Professor, Teacher, Drug Company, Government etc. and yeah what field as well.

 

[emzie]

Do you believe that Humans and Chimps will be able to hybridise, since they are our "closest relative"?

I'd want to know more about how close, in time scale, some other mammalian hybrids' parents are before I really get into the chimp-human question.

Some bizarre stuff in the USSR aside, as far as I'm aware, there's been very little in the way of attempts.

No.
In general, and I'm borrowing from the biology department here, you have to be in the same genus to be able to crossbreed.
The liger is from two parents of the same genus, as is the mule, for example.
Chimps and humans share the family, but not the genus.

It's really important to remember taxonomy is artificial and reflects our attempt to categorize the world, rather than reflecting the world. As a simple counter example to your definition, bottlenose dolphins and false killer whales are in different genera, but can have fertile offspring.

You can make a pretty good case that chimps belong in the same genus as us. If the taxonomy had been made by non-humans, I expect we would be in the same family as chimps.

What jobs do the biologists here have/want in the future?

Biology teacher.

What are these effects? I'm not aware of much of a role for quantum effects in biology. I did read a paper ages ago by an old Nobel prize winner that postulated things he called dendrons and psychons having quantum interactions (I think he was loosing it). From the paper:

As El_Mach said, quantum effects manifest themselves in how animals orient themselves to the earth's magnetic field. Or so it's thought.

 

[Andvare]

What jobs do the biologists here have/want in the future?

I just want to go back into the lab.

It is quite interesting how the things we take for granted were found out and how much of the significance of their research was grasped back then. And it lets you spam more references in the introduction of your thesis

My question:
As the first examples of quantum effects in biology have been found, how much of a role does quantum physics play in biological systems in your opinion?

Depending on what you mean by it, because all chemical interaction is a quantum interaction.

It's really important to remember taxonomy is artificial and reflects our attempt to categorize the world, rather than reflecting the world. As a simple counter example to your definition, bottlenose dolphins and false killer whales are in different genera, but can have fertile offspring.

Well, yes, but it's easier to explain that way, and the different families usually have reproduction that is not mixable. In general, which is why I used that word, it is true.

 

[Algeroth]

What jobs do the biologists here have/want in the future?

I hope to became researcher either at my university or at Academy of Science.

 

[El_Machinae]

Mainly visual detection of magnetic fields. But photosythesis requires quantum effects for energy transfer

For more information.

Seth Lloyd discusses this at a MIT


Link to video.

The story on red foxes using quantum effects to aid hunting was on Quirks & Quarks podcast and is available in their Jan 29, 2011 segmented episodes archive.


Honestly, quantum effects are a real thing, just like chemistry and biochemistry are. It's not really a surprise that convergent evolution makes use of these effects. What's probably cooler is our ability to notice!

 

[The_J]

Nothing implied. Just what are you looking for- Professor, Teacher, Drug Company, Government etc. and yeah what field as well.

I hope I can find a Ph.D students position in the next time...no luck at the moment :/.
Want to be at a scientific institute, and the field of work doesn't really matter, just should not be too specialized.


Oh, why that question ?

 

[Mark1031]

I hope I can find a Ph.D students position in the next time...no luck at the moment :/.
Want to be at a scientific institute, and the field of work doesn't really matter, just should not be too specialized.


Oh, why that question ?

I ask because I am a professional "biologist" myself. (I'm a Neuroscience Professor who primairly does basic research) and I'm curious what other people envision for a profession in science. Just the term biologist seems much too general to me as a profession. If you want to work at a scientific institute or do basic research you will be specialized. You may do different techniques but it is not like you will do immunology one day and ecology another. People who get a BS tend to do either Drug company/biotech research or sales or teacher. PhDs all want to be Professors but that is a long hard road esp today. It is a very tight job market.

 

[Algeroth]

If you want to work at a scientific institute or do basic research you will be specialized. You may do different techniques but it is not like you will do immunology one day and ecology another.

Yeah, I will stick with the ecology as long as I can. I known "biologist" is a broad term, but I started this thread with request for "Ask an Evolutionary Biologist" and it come to me as rather niche thread. I was surprised how many biologist (or nearly biologist) have shown up here.

 

[The_J]

I ask because I am a professional "biologist" myself. (I'm a Neuroscience Professor who primairly does basic research) and I'm curious what other people envision for a profession in science. Just the term biologist seems much too general to me as a profession. If you want to work at a scientific institute or do basic research you will be specialized. You may do different techniques but it is not like you will do immunology one day and ecology another. People who get a BS tend to do either Drug company/biotech research or sales or teacher. PhDs all want to be Professors but that is a long hard road esp today. It is a very tight job market.

Specialized was maybe the wrong word. Narrow is maybe better.
e.g. there's an open position at one university, and the topic is all about Rye genetics.

I mean, if it was about crop in general, but only Rye? No, that's too narrow. Sounds boring. I've read job offers which say "we're focusing on never-heard-protein X from unknown species Y with buzzword-technology Z"....yeah...no way I'll apply there. That's too narrow. The context is lost, so there's no real meaning anymore. No way.

----------

Don't want to be a professor, but well...who knows what the future will bring?

 

[Mark1031]

Yeah, I will stick with the ecology as long as I can.

What kind of job do you envision and how easy is it to get. For ecology I can imagine government land management type positions a few research jobs or teaching. I don't want to sound like your mother but an interesting question in the US is are we training too many scientists. I think the answer is yes for the jobs available, particularly in biomedical sciences.

I'm all for science training but you need to have the jobs at the end of the line.

 

[emzie]

I'd study ethology even if my job prospects were fast food.

 

[Mark1031]

I'd study ethology even if my job prospects were fast food.

I think you can shoot higher than that. I certainly think everyone should have more knowledge of science even if they don't use it professionally. But for many people it is dissappointing to not use their training in their ultimate profession.

 

[Algeroth]

What kind of job do you envision and how easy is it to get. For ecology I can imagine government land management type positions a few research jobs or teaching. I don't want to sound like your mother but an interesting question in the US is are we training too many scientists. I think the answer is yes for the jobs available, particularly in biomedical sciences.

I'm all for science training but you need to have the jobs at the end of the line.

The idea of "practical Bachelor degree." never really caught here, Bologna process was implemented because we had to. I'm kinda supposed to finish a PhD and continue on some research job.

If I would quit before, some land management or water quality control job is definetly possibility, probably in private sphere, not in government, there is a demand for people to work on recultivation or water treatment. But it if come to this, I would try to cash on my second degree in politology that I pursue parallel to my first one (long story) and try to get in journalism, I could get an recommendation from the woman that taught our journalist course.

(And teaching is always a possibility, I tried to teach few lessons on my former gymnasium. Everything went better than expected, but I'm still not convinced that I'm right for this job.)

 

[Algeroth]

I know I'm asking about some very elementary stuff, but could someone explain to ecologist what's the difference between Kimura Neutral theory of molecular evolution and Okamura Neary neutral theory of molecular evolution in regards to effect of population size to speed of evolution?

 

[GoodGame]

Impossible with current understanding of molecular biology and embryology.

DNA is a rather unstable molecule that degrades rapidly when its host dies. Under ideal conditions, a genome can remain intact for a few hundred thousand years in permafrost. but at time frames going back to dinosaurs, you won't find any usable DNA, even in amber.

Not too long ago, a paper made waves claiming to have found proteins in dinosaur fossils. From a protein, one could recreate a DNA sequence, though that's like saying we recovered one fragment sentence from the Bible. It's not going to tell you much of the story. I was pretty skeptical of the paper when I first read it though, so I'm not even sure the proteins will turn out to be a real find.

<snip>

There was a popular science book on the idea of making a chimera from re-sequenced DNA and inserting it into a chicken genome. Not a true Jurassic Park scenario, but similar to the idea of making chimeras based on elephants with contributions from mammoth DNA. Given the complexity of gene regulation inherent in the genome which would be lost by only having spliced proteins and not the original DNA, it's a pretty suspect scheme.



EDIT I read the thread again and realized Contre (and I) already mentioned this.

I know I'm asking about some very elementary stuff, but could someone explain to ecologist what's the difference between Kimura Neutral theory of molecular evolution and Okamura Neary neutral theory of molecular evolution in regards to effect of population size to speed of evolution?

Do you have a reference for the Okamura Neary theory? I've never heard of it. Kimura appears to be the first proponent of neutral evolution by accumulation of molecular mutations. Maybe you mean neutral evolution vs "nearly neutral" evolution?

I have a cite for Kimura here: http://www.eebweb.arizona.edu/Courses/Ecol426_526/Kimura_1968.pdf
And then there is King and Jukes a year later: (don't have an abstract, just wikipedia: http://en.wikipedia.org/wiki/Non-Darwinian_Evolution )

Ohta follows with a "nearly neutral" theory in which some neutral evolutions have minor changes that aren't completely neutral (e.g. small substitutions that might have small modest influences on traits), like making a single amino acid substitution or a single base substitution in a regulatory sequence (not sure if they new about those back then) to affect kinetics of molecules and their ultimate adaptive value.
Ohta reference: http://www.nature.com/nature/journal/v246/n5428/pdf/246096a0.pdf


I get the impression that there is a positive correlation (from skim reading the Ohta reference), and non-linear rate, between population size and the rate of evolution for positively selected traits. And the nearly neutral model allows for more of a selection gradient for traits that are classified as "neutral" than the neutral model allows, and the neutral model implies very few traits are ever positively selected for, so I'd think a nearly neutral model would predict a faster rate of evolution than a neutral only model (because nearly neutral allows for a larger number of traits having at least some adaptive value; but I don't know if there is a formula to demonstrate this, I'm intuiting this from a non-math comparison of the two models. And increasing the population size would just increase the rate of evolution for either model.

Question for the other biologists here: have any of you actually read Origin of Species?

No, other than ordered to read excerpts of that and the Descent of Man for a short paper. I'll admit I've read more pages of the bible ( ).
Origin of Species is free here with lots of other original manuscripts by Darwin: http://darwin-online.org.uk/converted/pdf/1876_Origin_F401.pdf

 

[Algeroth]

Do you have a reference for the Okamura Neary theory? I've never heard of it. Kimura appears to be the first proponent of neutral evolution by accumulation of molecular mutations. Maybe you mean neutral evolution vs "nearly neutral" evolution?

I have a cite for Kimura here: http://www.eebweb.arizona.edu/Courses/Ecol426_526/Kimura_1968.pdf
And then there is King and Jukes a year later: (don't have an abstract, just wikipedia: http://en.wikipedia.org/wiki/Non-Darwinian_Evolution )

Ohta follows with a "nearly neutral" theory in which some neutral evolutions have minor changes that aren't completely neutral (e.g. small substitutions that might have small modest influences on traits), like making a single amino acid substitution or a single base substitution in a regulatory sequence (not sure if they new about those back then) to affect kinetics of molecules and their ultimate adaptive value.
Ohta reference: http://www.nature.com/nature/journal/v246/n5428/pdf/246096a0.pdf


I get the impression that there is a positive correlation (from skim reading the Ohta reference), and non-linear rate, between population size and the rate of evolution for positively selected traits. And the nearly neutral model allows for more of a selection gradient for traits that are classified as "neutral" than the neutral model allows, and the neutral model implies very few traits are ever positively selected for, so I'd think a nearly neutral model would predict a faster rate of evolution than a neutral only model (because nearly neutral allows for a larger number of traits having at least some adaptive value; but I don't know if there is a formula to demonstrate this, I'm intuiting this from a non-math comparison of the two models. And increasing the population size would just increase the rate of evolution for either model.

Of course I meant Ohta and nearly neutral theory, sorry for the brainfart.

Source of my confusion is this paper by Ohta: http://ib.berkeley.edu/labs/slatkin/popgenjclub/pdf/ohta-gillespie1996.pdf where it wrotes

"If such borderline mutations or nearly
neutral mutations constitute a substantial fraction of new mutations,
theoretical predictions on the rate and pattern of evolution and
polymorphism become different from the neutral prediction. The most
notable difference is that there will be a negative correlation between the
evolutionary rate and the species population size. For neutral mutations,
the evolutionary rate is independent of the population size."

But then i come to sources that states that:

The rate of fixation of slightly negative mutations (k) or, to be more exact, the percentage of negative mutations that fall in the category of slightly negative mutations acting as effectively neutral mutations, is inversely proportional to the effective size of the population. Organisms with a long generation time, i.e. in general large organisms, mostly have a substantially smaller effective population size than organisms with a short generation time. Consequently, a greater fraction of nonsynonymous mutations fall in the category of selectively neutral for them and thus they have an overall larger fixation rate. As a consequence, the effect of the generation time on the number of mutations formed per year (negative) and the effect of the generation time on the rate of their fixation (positive) are mutually cancelled out for mutations in the coding region.

http://www.frozenevolution.com/nearly-neutral-theory-molecular-evolution

That's what leave me confused.