Evolution questions: round 3

[johnhanks]

My question is how did seeds evolve.

Pace pw, a few observations here.

First, I don't think Pegg is interested in a blow-by-blow account of the steps in the evolution of the seed habit, or even in an outline. My suspicion is that she has read somewhere that the evolutionary origin of seed plants has not been fully worked out, and that her question is an attempt at a 'gotcha!'.

Her last attempted gotcha related to evolutionary time and mutation rates: it was quickly disposed of, and Pegg has not returned to it.

As far as this one is concerned, it does not undermine the theory of evolution in the slightest to acknowledge that the origin of the seed habit is still quite obscure. Some major steps in the process, such as the evolution of heterospory and later endospory, have been known for decades, but there are still arguments over quite major details such as the exact origin of the endosperm. This site provides an excellent summary, but I suspect that the only sentence that will interest Pegg is

Note that at the present time the issue of seed plant evolution remains unsolved.

And so it does; but the ToE does not crumble into dust as a result.

 

[painted wolf]

To be more precise, What would cause them to develop? They show up in far more than just humans. How were they involved with survival? What would cause them to mutate into existence?

Anything that helps cells communicate faster is beneficial to survival... using lipids as well as neurotransmitters in cellular communication is very useful as neurotransmitters are better suited to long distance and long term communications while lipids can be produced quickly and discarded when not needed.

They mutate just like any other protein does. Some new protein configurations are useful and others aren't. Prions for example are non-beneficial mutant proteins.

wa:do

 

[painted wolf]

My question is how did seeds evolve.

This is an exciting subject in evolutionary study... It is really at the cutting edge of our knowledge and unfortunately I'm not as well versed in botany to really do the subject justice.

However...

in 2004 a fossil of Runcaria heinzelinii was found in Belgium in rocks only 20 million years before the first true seeds have been commonly found. This early plant is a transitional fossil between spore producing plants and the earliest true seed bearing plants.

It is essentially a "half seed". Now that we have a better idea where and when to look for more fossils we should be getting a clearer picture of exactly how this evolutionary step happened.

The emergence of the seed habit in the Middle Paleozoic was a decisive evolutionary breakthrough. Today, seed plants are the most successful plant lineage, with more than 250,000 living species. We have identified a middle Givetian (385 million years ago) seed precursor from Belgium predating the earliest seeds by about 20 million years. Runcaria is a small, radially symmetrical, integumented megasporangium surrounded by a cupule. The megasporangium bears an unopened distal extension protruding above the multilobed integument. This extension is assumed to be involved in anemophilous pollination. Runcaria sheds new light on the sequence of character acquisition leading to the seed.

Runcaria, a Middle Devonian Seed Plant Precursor
More can be found here:
http://www.sciencemag.org/content/suppl/2004/10/27/306.5697.856.DC1/Gerrienne.SOM.pdf
The significance of Runcaria (Middle Devonian, Belgium) in the evolution of seed plants

In addition genetic studies are helping to clear up what mutations were involved in going from spores to seeds.

It will be exciting to see what new fossils are found and how they can help provide a better understanding of this highly significant development.

wa:do

 

[terryboy]

Ok... so I've had two of these up before:
http://www.religiousforums.com/forum/evolution-vs-creationism/94931-ask-biologist-19.html
http://www.religiousforums.com/foru...onism/79784-questions-about-evolution-24.html

And it looks like we have some new people around who may want to ask questions on how evolution works and what it actually says. Got a good handle on Evolution and want a point clarified... I'll see what I can do!

So, have fun... all honest questions are welcome!

My updated credentials... I have my Bachelors in Biology now and I'm working on my research proposal and other needed papers for getting into a PhD program in Evolutionary studies/Paleontology. Though my plans have been delayed for family reasons, with any luck, this time next year I should be sending off applications.
I have taught/or assisted labs on general science and basic evolutionary theory as well as tutoring in several biology subjects.

I only have one publication to my name at this point (a poster on Horseshoe Crab population genetics)
I'm still a geek who loves reading primary literature, but I sneak in the odd pop-sci book for variety.

wa:do

My question is,

how did the mammals evolved to be cuter than the reptiles?

Thanks!

 

[painted wolf]

My question is,

how did the mammals evolved to be cuter than the reptiles?

Thanks!

What blasphemy is this?

wa:do

 

[terryboy]

That amphibian looks cute but the reptile! Eeeek!!!

they can't beat this!

 

[painted wolf]

No amphibians in my pics... members of three of the four main groups of "reptiles". A turtle, a croc and a lizard.

Amphibians are adorable too...

Biologically what is happening is that we have a cognitive bias that wires us to see things with large heads and big eyes as "cute"... the closer the features approximate human infants the "cuter" the critter is.
Which is why dogs like pugs are so iconic as "cute"... though, I tend to find them disturbing anatomically. These critters trigger serotonin production in the brain and make us "happy".

wa:do

ps... in the frog and lizard, bright colors help too... bright colors are more "attractive" than dull ones.

 

[Photonic]

No amphibians in my pics... members of three of the four main groups of "reptiles". A turtle, a croc and a lizard.

Amphibians are adorable too...

Biologically what is happening is that we have a cognitive bias that wires us to see things with large heads and big eyes as "cute"... the closer the features approximate human infants the "cuter" the critter is.
Which is why dogs like pugs are so iconic as "cute"... though, I tend to find them disturbing anatomically. These critters trigger serotonin production in the brain and make us "happy".

wa:do

ps... in the frog and lizard, bright colors help too... bright colors are more "attractive" than dull ones.

Bright colors can also mean they are incredibly dangerous.

 

[Koldo]

Bright colors can also mean they are incredibly dangerous.

And that's the nature's sense of humour.

What a cute little frog, isn't it?
*super poisonous!!*

 

[terryboy]

And that's the nature's sense of humour.

What a cute little frog, isn't it?
*super poisonous!!*

Does cuteness have anything to do with evolution? Do animals perceive cuteness like we do?

 

[painted wolf]

Hard to say... though most animals have visual objectivity when looking for mates.

Most female birds for example base mate choice largely on plumage... birds with yellows, reds and oranges get these colors from their food so, brighter colors often indicate health.

Another example in birds... in many birds parents feed their young based on color cues from the open mouths of their chicks. The chick with the brightest mouth tends to get the most food... and parents will keep feeding as long as they see the cue, it's a hard-wired behavior.

wa:do

 

[idav]

Does cuteness have anything to do with evolution? Do animals perceive cuteness like we do?

I think so. I kinda get the idea that cuteness has a lot to do with being youthful looking. Babies, puppies, kittens and most all other young animals are much cuter than their older counter parts. I suppose cuteness could be a factor animals protecting their young, that is if they didn't find the young one too appetizing.

 

[painted wolf]

Babies release "happy" hormones into adult brains. That has a bit to do with it.

wa:do

 

[Mcshane22]

No amphibians in my pics... members of three of the four main groups of "reptiles". A turtle, a croc and

Biologically what is happening is that we have a cognitive bias that wires us to see things with large heads and big eyes as "cute"... the closer the features approximate human infants the "cuter" the critter is.
Which is why dogs like pugs are so iconic as "cute"... though, I tend to find them disturbing anatomically. These critters trigger serotonin production in the brain and make us "happy".

wa:do

ps... in the frog and lizard, bright colors help too... bright colors are more "attractive" than dull ones.

Your explanation is great and it can be seen in children's cartoons as to what features the cartoonist over emphasize such as large eyes and heads that are larger then the body

 

[terryboy]

I think so. I kinda get the idea that cuteness has a lot to do with being youthful looking. Babies, puppies, kittens and most all other young animals are much cuter than their older counter parts. I suppose cuteness could be a factor animals protecting their young, that is if they didn't find the young one too appetizing.

I agree with you, it's such a marvel that some animals (mammals particularly) evolved to have 'feelings' for the young. I'm wondering how genetic could control something like that.

 

[shawn001]

A Love Drug? Oxytocin Hormone Makes Mothers Kinder

"
Sometimes it seems like what the world really needs is a love drug. But what if we could just produce it in our own brains, making humans more altruistic and interested in helping others, and paving the way for a new mother to give her baby the warm embrace it so desperately needs?
Well, we already do, according to scientists who are studying a hormone produced in the brains of mammals ranging from prairie voles to humans. It is officially known as oxytocin, but it is also called the "love hormone," the "cuddle chemical," and the "hormone of love and bonding."

A Love Drug? Oxytocin Hormone Makes Mothers Kinder - Yahoo!

 

[painted wolf]

I agree with you, it's such a marvel that some animals (mammals particularly) evolved to have 'feelings' for the young. I'm wondering how genetic could control something like that.

Parents that care for their offspring have better chances of having offspring that survives.

Genes that control the sensitivity and production of chemicals like oxytocin in relation to the rearing of young are thus more likely to be passed down.

wa:do

 

[terryboy]

Ok Next question,

Why are moths attracted to light? did they evolved to be attracted to light?

 

[shawn001]

Ok Next question,

Why are moths attracted to light? did they evolved to be attracted to light?

FYI

Probing Question: Why are moths attracted to light?

HowStuffWorks "Why are moths attracted to light?"

 

[painted wolf]

Ok Next question,

Why are moths attracted to light? did they evolved to be attracted to light?

Lot's of critters are essentially hard wired to respond to light... with moths its an attraction, mostly to the UV end of the spectrum. (so for example a low UV light source will attract fewer, if any, moths)

I don't know why they evolved the attraction, but there are some hypotheses about it. Usually involving the fact that bright artificial lights simply overstimulates the otherwise subtle natural attractions.

The natural attraction may have to do with either navigation or predator avoidance. Navigation by moon and stars is pretty common among animals and lots of night flying navigators are known to be fooled by bright artificial lights.
Also, when avoiding predators you don't want to go toward a dark shape because that could be another predator... so you head toward the light.

Either way, overstimulation of these triggers may cause a more profound response to the stimuli. One example of this is how songbirds respond to the color red in a chicks mouth, the brighter and bigger the patch of red, the more and faster the parent will provide food. This is why songbirds will keep feeding a cuckoo chick who is obviously not theirs.

wa:do