nPeace
Veteran Member
Claim? Support what? That the neurons, and synapses have a particular goal.What "goal"?
I'm not claiming any goals at all. I have no clue why you think that I am.
You keep claiming that. Are you going to support it, or are you just going to keep claiming it?
I'll ignore that, since you can't be serious... and I don't think it's not that you are not paying attention.
You have not explained anything.Bare claims aren't evidence of anything. Except perhaps gullibility.
I already told you: patterns and processes that emerge from the laws of nature working on matter.
Can you give an example?
Yes. The existing brain with all its components in place, does.Yes. The brain is a pattern of matter and this pattern triggers chemical processes.
Columbus.Adapation = evolution.
You did mention the assumptions you have, yes.Reproduce, mutate, survive, repeat.
I already told you how we know that brain building is regulated by genetics, how brains size is regulated by genetics, how variation of brain size is regulated by genetic mutation, how we have plenty of examples of extant species that have extremely simple rudimentary brains all the way upto species with large complex brains, how we know from the fossil record that brains of the human lineage have gradually grown bigger over the past couple million years.
Inference and presuppositions are what you accuse us of making. So why do you feel you are in a better position to use them?
It is written in your books. You must infer, and presume. You cannot directly observe this, and make verifiable conclusions.We also know that natural processes can and do result in natural design all the time.
You being ignorant (or too stubborn to learn) about that, doesn't change that fact.
Never said it was.
Bare claim again.
Not an assumption.
View attachment 44344
Not an assumption.
Factually, throughout the animal kingdom, we have examples of very small and simple rudimentary brains all the way up to the large complex human brain and plenty of examples in between.
Kind of strange that you would call that an "assumption".
The alternative to this factoid would be to claim that all animals have a brain of the same size and complexity. Clearly that is not the case.
Progress in the study of brain evolution: from speculative theories to testable hypotheses
Darwin's theory of evolution raised the question of how the human brain differs from that of other animals and how it is the same. Early students of brain evolution had constructed rather grand but speculative theories which stated that brains evolved in a linear manner, from fish to man and from simple to complex. These speculations were soundly refuted, however, as contemporary comparative neurobiologists used powerful new techniques and methodologies to discover that complex brains have evolved several times independently among vertebrates (e.g., within teleost fishes and birds) and that brain complexity has actually decreased in the lineages leading to modern salamanders and lungfishes. Moreover, the old idea that brains evolved by the sequential addition of new components has now been replaced by the working hypothesis that brains generally evolve by the divergent modification of preexisting parts. Speculative theories have thus been replaced by testable hypotheses, and current efforts in the field are aimed at making phylogenetic hypotheses even more testable. Particularly promising new directions for comparative neurobiology include (1) the integration of comparative neuroanatomy with comparative embryology and developmental genetics in order to test phylogenetic hypotheses at a mechanistic level, (2) research into how evolutionary changes in the structure of neural circuits are related to evolutionary changes in circuit function and animal behavior, and (3) the analysis of independently evolved similarities to discover general rules about how brains may or may not change during the course of evolution.
Is that article too old?
In search of a unifying theory of complex brain evolution
How does evolution produce a complex brain? What are the factors that contribute to aspects of cortical expansion and organization in different mammals? How did human brains become so large and complex, and are they fundamentally different than the brains of other mammals? While these questions are inherently interesting, generating theories about brain evolution is a tricky business because one must strike a balance between known experimental data from extant mammals and inferences that can be made from these data regarding the unknown form of ancestral brains. For this reason, studies of brain evolution have not been at the forefront of neuroscience research until quite recently. Without question, it can be more rewarding to directly record from a neuron and characterize its response properties, or identify cells on a microscope than to assemble data from diverse disciplines to weave a cohesive story about a process that has been occurring for over 4 billion years.
Yes. You have ideas, but they are just that... ideas.
Why are there so many explanations for primate brain evolution?
The question as to why primates have evolved unusually large brains has received much attention, with many alternative proposals all supported by evidence. We review the main hypotheses, the assumptions they make and the evidence for and against them. Taking as our starting point the fact that every hypothesis has sound empirical evidence to support it, we argue that the hypotheses are best interpreted in terms of a framework of evolutionary causes (selection factors), consequences (evolutionary windows of opportunity) and constraints (usually physiological limitations requiring resolution if large brains are to evolve). Explanations for brain evolution in birds and mammals generally, and primates in particular, have to be seen against the backdrop of the challenges involved with the evolution of coordinated, cohesive, bonded social groups that require novel social behaviours for their resolution, together with the specialized cognition and neural substrates that underpin this.
A study? Who is talking about a study?If you wish to call embryology "unscientific".
Methods are use in science fields of study. They are not unscientific... but the assumptions and conclusions reached based on these assumption are... as there are some things you cannot verify conclusively.
I already linked to papers showing that comparative anatomy, or genetics are based on interpretations which are not foregone conclusions.
A child. I know of no child that does not have brain cells, unless something went horribly wrong.High school biology.
I wasn't talking about brain evolution. I was talking about the buildup / growth of the brain during embryonic development. In the beginning of pregnancy, the "child" doesn't have a brain or braincells. And then a couple months later, it does. Are you not aware of this?
Genes play a role in growth in the body. I fail to see what that has to do with the fact that assumptions prove nothing.The fact that mutations can make brain sizes vary, is what matters.
Not all mutations are going to have the same ripple effects. What it proves, is that brain size not only can be, but IS, regulated/determined by genetics.
This seems quite off topic.Picking on those mutations that also have harmful side-effects, doesn't change that fact.
Also not that most mutations, even beneficial ones, oftenly come with a cost. It's usually a tradeoff if the benefit outweighs the cost.
For example....
Consider a mutation that increases bone density by loading it up with more calcium.
Suppose this happens in a species that benefits from it.
That calcium needs to come from somewhere...
So, either it needs to alter its diet so that it takes up more calcium. Or the calcium is to be taken from elsewhere in the body, meaning that there is less calcium available now for other stuff.
In case of the latter, the benefit of stronger bones must outweigh the loss of calcium in those other systems.
Having said that... ever wondered why wisdom teeth hurt like hell and why most people need to have them pulled out? I'll tell you: because our mouth is too small for all our teeth. We used to have bigger mouth, with enough room for all those teeth. But our brain exploded in size. Today, our cranium takes up more room. And analogous to the calcium in the above example, that room needs to be taken from somewhere: our mouth. A bigger head isn't an option as that would give problems for childbirth.
So today, due to a brain that trippled in size in only a couple million years, we have a mouth that is too small to house all our teeth.
See, how all that stuff neatly comes together to form a bigger picture? That's what they call "explanatory power".
Now you can try and explain how an "intelligent designer" apparently was so dumb that he gave us a set of teeth with a mouth to small to fit all of them.
Or you can let go of this iron age superstition and read up on modern 21st century biology.
It's your choice off course.
What are we talking about again?Don't confuse the "how" with the "if".
Determining that a structure evolved is not the same as finding out the exact evolutionary path that was taken to end up with said structure.
As an analogy... let's go to Lenski's E.Coli experiment.
12 populations, non of which are able to metabolize citrate. Physically impossible to do so.
After x generations, 1 population has a population explosion. Turns out, they are feeding on citrate and that novel food source means an abundance of food, leading to a larger population size that can be sustained.
Nobody went into that population to fiddle around with the genes to create this metabolic pathway.
So, they KNEW the feature evolved. But they didn't know HOW yet.
They then went back to previous generations (they kept samples in a freezer so that they could trace it back if such things happened). And by doing so, they were able to identify exactly which mutations were responsible for it.
So there you go.....
Determining that a structure evolved without knowing how it evolved - perfectly possible.
Is the OP about evidence for God's existence? Should you be talking about evolution, or how life came to be?
Last edited: