The evolution of the brain and nervous system, and the mind and consciousness

[Nous]

This is a summary reference with tables. Yes, the gradual evolution of the brain and nervous system specifically show progressive evidence of the mind and consciousness. Fro example. Advanced evolution of mammals do dream, and even some evidence that some reptiles may also dream based on their sleep patterns the same as mammals that are known to dream..

From: Do Reptiles Dream? New Study Suggests The Animals Experience REM Sleep

Lizards sleep in a series of stages, such as Do Reptiles Dream? New Study Suggests The Animals Experience REM Sleep movement (REM) sleep, much like human beings, according to new research. The study even indicated the creatures may dream.

Australian bearded dragons were examined as part of the new study. Investigators were able to show the animals experienced sleep in much the same way as our own species.

This marks the first time any major study has documented proof that lizards sleep in stages, including slow-wave sleep and REM. It is during this latter stage of sleep that most dreaming takes place. Before this recent study, only mammals and birds were shown to exhibit such behavior.

The subjects of a reptile's dream remains a mystery, although the possibilities remain intriguing.

"If you forced me to speculate and to use a loose definition of dreaming, I'd speculate that those dreams are about recent notable events: insects, maybe a place where there are good insects, an aggressive male in the next terrarium, et cetera. If I were an Australian dragon living in Frankfurt, I'd be dreaming of a warm day in the sun," saidGilles Laurent, a neuroscientist from the Max Planck Institute for Brain Research in Germany.

While REM sleep is marked by increased heart rate, blood pressure and dreaming, slow-wave sleep is just the opposite. During this most-restful period of sleep, little dreaming occurs, and brain activity, dominated by delta waves, is reduced.


Humans typically experience REM sleep four to five times each night. Electrodes placed inside the brains of the lizards revealed Pogona vitticeps experienced the effect around 350 times during each period of sleep. These stages lasted an average of just 80 seconds each time.

This discovery suggests that sleep patterns seen in humans and birds evolved 100 million years earlier than previously believed. Researchers believe the behavior likely first evolved in amniotes, a distant common ancestor of lizards, birds, and mammals, which lived between 300 million and 320 million years before our own time.

Nearly all animals sleep, although methods and behaviors during the process differ between species. Animals that do not sleep include dolphins and bullfrogs.

Analysis of the sleep patterns of lizards, and what the discovery can tell us about the evolution of animals, was published in the journal Science.

Again, in order to test a hypothesis about "degree" vs. "kind" with respect to "experience," one would need to define those terms. Right?

This is the earliest stages of the evolution of the brain, and not the frontal lobe. First things first.

I don't know what you're trying to say here. The frontal lobe was not present at "the earliest point of vertebrate brain evolution," as far as I know.

 

[sealchan]

Second half of the above:

From: Evolution of Consciousness: Phylogeny, Ontogeny, and Emergence from General Anesthesia - In the Light of Evolution - NCBI Bookshelf

"Thalamocortical oscillations have been posited to be of critical importance to consciousness because they help integrate functionally diverse and spatially distinct cognitive modules in the cortex (Saalmann et al., 2012; Schmid et al., 2012). The interplay of segregation and integration is a fundamental focus of the integrated information theory of consciousness (Tononi, 2004, 2012). The capacity of the thalamocortical system to achieve both integration and differentiation is reflected in higher levels of Phi, a proposed metric for consciousness (Tononi, 2004). Phi reflects the amount of information generated by an integrated system beyond the information contained within the components of the system. In principle, this measure captures the emergent property of the system (consciousness) that cannot be causally reduced to individual subsystems (particular brain regions). Phi is predicted to decrease during sleep and seizures; preliminary evidence suggests it also decreases during anesthesia (Lee et al., 2009b), possibly due to impaired long-range coupling of neural spike activity (Lewis et al., 2012). Although the integrated information theory of consciousness has yet to be definitively demonstrated, it is a guiding paradigm that can inform the evolution of consciousness from the network perspective. Creatures with brain network systems that are capable of generating high values of Phi are more likely to be conscious (Edlund et al., 2011).

So they can measure a certain type of brain activity, widespread activation across the cortex, as Phi and then using that in a quantitative way to predict the level of consciousness of an organism individually or on the whole. That sounds like a good experimental basis to make good progress.

Third, widespread brain activity appears correlated with conscious activity. Sensory input spreads quickly from sensory cortex to parietal, temporal, and prefrontal areas (Dehaene et al., 2003). This spread of cortical activity is also associated with recurrent local feedback occurring along the way, followed shortly thereafter by long-range feedback from anterior to posterior structures (Lamme, 2006). These long-range connections are thought to be important for the experiential aspects of consciousness (i.e., awareness) (Singer, 1993) and appear to be preferentially suppressed during general anesthesia (Lewis et al., 2012; Schröter et al., 2012). In particular, there is strong evidence that networks across the frontal and parietal cortices are associated with awareness across multiple sensory modalities (Gaillard et al., 2006; Fahrenfort et al., 2008; Blumenfeld, 2012). The lateral frontoparietal network plays a role in mediating consciousness of the environment, whereas the medial frontoparietal network plays a role in mediating internal conscious states such as dreaming and internally directed attention (Boly et al., 2007; Denton et al., 2009). It is becoming increasingly clear that the directionality of corticocortical network communication is relevant to conscious processing. Information processing from the caudal to rostral direction (feedforward) is associated with sensory processing that can occur in the absence of consciousness (e.g., general anesthesia, priming) (Imas et al., 2005; Gaillard et al., 2007). In contrast, information processing in the rostral-to-caudal direction (feedback or cortical reafference) is thought to be associated with experience itself and is preferentially inhibited by general anesthetics (Imas et al., 2005; Lee et al., 2009a; Ku et al., 2011).

This reminds me of Gerald Edelman (who I know has collaborated with Tononi). His model of re-entrant connections of neuronal groups which compete in an evolutionary-style competition seems to be reflected here. The cortex has these localized groups of neurons with strong connections internally that then also interface with other groups of neurons in perhaps one or more tiers of remoteness, say the cortical region is the next level of timely influence and then cross-cortical regions have the latest influence.

In Edelman's view of the "remembered present" the re-entrant (feedback) connections in the cortex are essential to consciousness perhaps because they facilitate an ability to not only shape incoming sensory information but produce it while asleep (sort of like an echo does by reflection). Without this ability of the brain to produce sensory like experiences internally independent of actual sensory input, there would be no sense of a "conscious model" of the world or the so-called "Cartesian theater".

The neocortical view of consciousness originates, in part, from early morphologic examination of brain differences across species that suggested the capacities of consciousness increased as brains evolved from more primitive reptilian organization, to mammalian (or, with a limbic system, paleomammalian), and then neo-mammalian organization, characterized by an intricately folded neocortex. This conceptualization of brain evolution occurring in stages during which more “advanced” brains—along with their expanded behavioral repertoire—were built on the structure of earlier forms was popularized by Maclean as “the triune brain” (Maclean, 1990). Importantly, this view of brain evolution is now largely considered erroneous (Emery and Clayton, 2005; Jarvis et al., 2005). It did offer an easy conceptualization for relating brain structure with function and suggested evolutionary time points for when various behaviors would have emerged. Newer findings, however, strongly refute the model of a triune brain, especially the concept of a later-developing neocortex (Fig. 3.1) (Emery and Clayton, 2005). As it turns out, a precursor of the neocortex was actually present in the earliest evolving vertebrates, a claim based on some aspects of connectivity and homology of early transcription factor expression (Striedter, 2005). The basic structural pattern of a brainstem, midbrain, and forebrain did not need to be completely reinvented as each new species emerged. Rather, as various ecological niches were exploited by various creatures, those brain regions best suited for enhancing survival in the local environment were emphasized for further development (Emery and Clayton, 2005).


FIGURE 3.1
Theories of brain evolution. Ancient brain structure evolution theory of Scala Naturae showing brain development proceeding from simple to more complicated with the addition of new brain regions as evolution progressed. This erroneous view is compared (more...)."

That seems to me to be a big theme in evolution...there is a very broad partially implicit template in the DNA of any organism that seems to allow for simple modifications to reach new adaptations and the tree of life as a whole provides many branch tips to use as a jumping off point for filling in the next available and unique niche. So human consciousness seems like some great leap in evolution...but really it is based on an already evolutionarily trained template of forms that requires minor adjustment for what might result in major outcomes (the influence of homo sapiens back on the ecology of the earth as a whole and a way of spreading that ecology beyond the earth).

Neurobiology is definitely an exciting branch of science to follow.

Thank you for this.

 

[sealchan]

This is a summary reference with tables. Yes, the gradual evolution of the brain and nervous system specifically show progressive evidence of the mind and consciousness. Fro example. Advanced evolution of mammals do dream, and even some evidence that some reptiles may also dream based on their sleep patterns the same as mammals that are known to dream..

From: Do Reptiles Dream? New Study Suggests The Animals Experience REM Sleep

Lizards sleep in a series of stages, such as Do Reptiles Dream? New Study Suggests The Animals Experience REM Sleep movement (REM) sleep, much like human beings, according to new research. The study even indicated the creatures may dream.

Australian bearded dragons were examined as part of the new study. Investigators were able to show the animals experienced sleep in much the same way as our own species.

This marks the first time any major study has documented proof that lizards sleep in stages, including slow-wave sleep and REM. It is during this latter stage of sleep that most dreaming takes place. Before this recent study, only mammals and birds were shown to exhibit such behavior.

The subjects of a reptile's dream remains a mystery, although the possibilities remain intriguing.

"If you forced me to speculate and to use a loose definition of dreaming, I'd speculate that those dreams are about recent notable events: insects, maybe a place where there are good insects, an aggressive male in the next terrarium, et cetera. If I were an Australian dragon living in Frankfurt, I'd be dreaming of a warm day in the sun," saidGilles Laurent, a neuroscientist from the Max Planck Institute for Brain Research in Germany.

While REM sleep is marked by increased heart rate, blood pressure and dreaming, slow-wave sleep is just the opposite. During this most-restful period of sleep, little dreaming occurs, and brain activity, dominated by delta waves, is reduced.


Humans typically experience REM sleep four to five times each night. Electrodes placed inside the brains of the lizards revealed Pogona vitticeps experienced the effect around 350 times during each period of sleep. These stages lasted an average of just 80 seconds each time.

This discovery suggests that sleep patterns seen in humans and birds evolved 100 million years earlier than previously believed. Researchers believe the behavior likely first evolved in amniotes, a distant common ancestor of lizards, birds, and mammals, which lived between 300 million and 320 million years before our own time.

Nearly all animals sleep, although methods and behaviors during the process differ between species. Animals that do not sleep include dolphins and bullfrogs.

Analysis of the sleep patterns of lizards, and what the discovery can tell us about the evolution of animals, was published in the journal Science.




This is the earliest stages of the evolution of the brain, and not the frontal lobe. First things first.

My understanding is that the authors of the paper suggest the frontal lobe has always been present but may have been so diminutive as to not be obvious. In evolutionary terms, adjusting the size of something is far, far easier than it is to invent something new.

 

[sealchan]

What I heard re: the science is that science is having trouble reconciling the existence of consciousness to naturalistic means/mechanisms.

That is like saying a marathon runner, most of the way through the race, is having trouble running that race.

 

[Polymath257]

Researchers have sent molecules containing 810 atoms (whose total mass was over 10,000 atomic mass units) through the so-called "double-slit experiment," showing that they cause an interference pattern that can only be explained if the particles act like waves of water, rather than tiny marbles.

Reference: Physicists Smash Record For Wave-Particle Duality – The Physics arXiv Blog – Medium

Eibenberger, Sandra; et al. (2013). "Matter-wave interference with particles selected from a molecular library with masses exceeding 10000 amu". Physical Chemistry Chemical Physics. 15 (35):1469614700. arXiv:1310.8343. Bibcode:2013PCCP...1514696E. doi:10.1039/C3CP51500A. PMID 23900710.

The behavior of a molecule weighing 10,000 atomc mass units is beyond the scope of quantum mechanics, ...right?

Wrong. Quantum mechanics is the fundamental theory. Classical mechanics is the approximation to QM. But in this experiment, there wasn't a single molecule of mass 10,000 AMU, but 810 atoms that add up to that mass. There is a significant difference.

But, yes, we would expect a 10,000 AMU molecule to have a wavelength. It would be small, but there.

 

[Polymath257]

The following article is a good introduction that outlines some of the supporting evidence for the evolution, and the present issues and limits of the present research. This is the first section of the article.

From: Evolution of Consciousness: Phylogeny, Ontogeny, and Emergence from General Anesthesia - In the Light of Evolution - NCBI Bookshelf

3Evolution of Consciousness: Phylogeny, Ontogeny, and Emergence from General Anesthesia
GEORGE A. MASHOUR* and MICHAEL T. ALKIRE†‡.

Author Information

Are animals conscious? If so, when did consciousness evolve? We address these long-standing and essential questions using a modern neuroscientific approach that draws on diverse fields such as consciousness studies, evolutionary neurobiology, animal psychology, and anesthesiology. We propose that the stepwise emergence from general anesthesia can serve as a reproducible model to study the evolution of consciousness across various species and use current data from anesthesiology to shed light on the phylogeny of consciousness. Ultimately, we conclude that the neurobiological structure of the vertebrate central nervous system is evolutionarily ancient and highly conserved across species and that the basic neurophysiologic mechanisms supporting consciousness in humans are found at the earliest points of vertebrate brain evolution. Thus, in agreement with Darwin's insight and the recent “Cambridge Declaration on Consciousness in Non-Human Animals,” a review of modern scientific data suggests that the differences between species in terms of the ability to experience the world is one of degree and not kind.

Evolutionary biology forms a cornerstone of the life sciences and thus the neurosciences, yet the emergence of consciousness during the timeline of evolution remains opaque. As the theory of evolution began to eclipse both religious explanations and Enlightenment doctrines regarding the singularity of human consciousness, it became clear that consciousness must have a point of emergence during evolution and that point likely occurred before Homo sapiens. “How,” Darwin questioned, “does consciousness commence?” His post-Beagle research on this question evidently caused him violent headaches. One such headache can be expressed as the 20th century philosophical distinction of phenomenal consciousness and access consciousness (Block, 2007). Phenomenal consciousness relates solely to subjective experience, whereas access consciousness includes (among other processes) the ability to report such experiences verbally (other distinctions related to consciousness can be found in Table 3.1). Thus, the scientist looking for objective indices of subjective events is primarily limited to humans manifesting access consciousness, an obstacle in studying the evolution of consciousness antecedent to our species. We could, however, take solace in the dictum that ontogeny recapitulates phylogeny and search for clues in developing humans. Unfortunately, Haeckel's theory of recapitulation is not scientifically sound and, even if applicable in this case, we would still be constrained by the high probability that babies develop phenomenal consciousness before access consciousness. To overcome the limitations in identifying the birth of consciousness, we need a reproducible experimental model in which (i) consciousness emerges from unconsciousness at a discrete and measurable point, (ii) phenomenal consciousness and access consciousness are closely juxtaposed or collapsed, and (iii) assessment of neural structure and function is possible. In this chapter, we consider top-down and bottom-up approaches to consciousness, nonhuman consciousness, and the emergence of consciousness from general anesthesia as a model for the evolution of subjectivity.

I am comfortable with saying most vertebrates are conscious, at least to some degree. But what about earthworms? or, to go farther back, how about planaria? jellyfish? Sponges?

I would be very hard pressed to claim that sponges or jellyfish are conscious. They simply don't have the neural support for such.

On the other hand, many insects seem to show the fundamentals of consciousness, although the pre-programmed behavior of some also might suggest otherwise.

 

[sealchan]

I quoted the post claiming that
"scientific data suggests (sic) that the differences between species in terms of the ability to experience the world is one of degree and not kind." From what data was that conclusion derived? Obviously in order to test a hypothesis about "degree" vs. "kind" with respect to "experience," one would need to define those terms. Right? No such data are cited at the blurb linked to.

I quoted the post claiming that "the basic neurophysiologic mechanisms supporting consciousness in humans are found at the earliest points of vertebrate brain evolution." But fish do not have frontal lobes.

Is this understood based on the skulls of these species or on a measurement of actual brain activity. Do these species have cerebral cortices? Is the frontal lobe merely the lobe at the front of an otherwise continuous sub-organ of the brain?

 

[sealchan]

I am comfortable with saying most vertebrates are conscious, at least to some degree. But what about earthworms? or, to go farther back, how about planaria? jellyfish? Sponges?

I would be very hard pressed to claim that sponges or jellyfish are conscious. They simply don't have the neural support for such.

On the other hand, many insects seem to show the fundamentals of consciousness, although the pre-programmed behavior of some also might suggest otherwise.

That is what is trying to be defined in this article. What can we actually look at to understand what is supportive on consciousness? The paper authors are suggesting that widespread brain activity correlation in connection with feedback neural connectivity would be a basis for some level of consciousness.

What also must be understood, or course, is "how many crayons are there in the crayon box" of a species consciousness. What means of acting on the world and discriminating sensory input on the world are available to this widely connected feedback inclusive neural network?

 

[Nous]

Is this understood based on the skulls of these species or on a measurement of actual brain activity. Do these species have cerebral cortices? Is the frontal lobe merely the lobe at the front of an otherwise continuous sub-organ of the brain?

Actually my comment was concluded from my inability to find any reference to a frontal lobe in fish.

 

[shunyadragon]

What I heard re: the science is that science is having trouble reconciling the existence of consciousness to naturalistic means/mechanisms.

This is not what the scientific references explain. It explains the advancements and problems. Of course, all questions have not answered, but 'arguing from ignorance' is not the answer.

 

[shunyadragon]

Actually my comment was concluded from my inability to find any reference to a frontal lobe in fish.

Specifically looking for one frontal lobe species does not address the issue of the evolution of the brain and nervous system over billions of years.

The size of frontal lobe has not been shown to be required for consciousness in animals, ie the presence of dreaming, and the ability of many cephlapods to manipulate their environment..

 

[sealchan]

This is a summary reference with tables. Yes, the gradual evolution of the brain and nervous system specifically show progressive evidence of the mind and consciousness. Fro example. Advanced evolution of mammals do dream, and even some evidence that some reptiles may also dream based on their sleep patterns the same as mammals that are known to dream..

From: Do Reptiles Dream? New Study Suggests The Animals Experience REM Sleep

Lizards sleep in a series of stages, such as Do Reptiles Dream? New Study Suggests The Animals Experience REM Sleep movement (REM) sleep, much like human beings, according to new research. The study even indicated the creatures may dream.

Australian bearded dragons were examined as part of the new study. Investigators were able to show the animals experienced sleep in much the same way as our own species.

This marks the first time any major study has documented proof that lizards sleep in stages, including slow-wave sleep and REM. It is during this latter stage of sleep that most dreaming takes place. Before this recent study, only mammals and birds were shown to exhibit such behavior.

The subjects of a reptile's dream remains a mystery, although the possibilities remain intriguing.

"If you forced me to speculate and to use a loose definition of dreaming, I'd speculate that those dreams are about recent notable events: insects, maybe a place where there are good insects, an aggressive male in the next terrarium, et cetera. If I were an Australian dragon living in Frankfurt, I'd be dreaming of a warm day in the sun," saidGilles Laurent, a neuroscientist from the Max Planck Institute for Brain Research in Germany.

While REM sleep is marked by increased heart rate, blood pressure and dreaming, slow-wave sleep is just the opposite. During this most-restful period of sleep, little dreaming occurs, and brain activity, dominated by delta waves, is reduced.


Humans typically experience REM sleep four to five times each night. Electrodes placed inside the brains of the lizards revealed Pogona vitticeps experienced the effect around 350 times during each period of sleep. These stages lasted an average of just 80 seconds each time.

This discovery suggests that sleep patterns seen in humans and birds evolved 100 million years earlier than previously believed. Researchers believe the behavior likely first evolved in amniotes, a distant common ancestor of lizards, birds, and mammals, which lived between 300 million and 320 million years before our own time.

Nearly all animals sleep, although methods and behaviors during the process differ between species. Animals that do not sleep include dolphins and bullfrogs.

Analysis of the sleep patterns of lizards, and what the discovery can tell us about the evolution of animals, was published in the journal Science.




This is the earliest stages of the evolution of the brain, and not the frontal lobe. First things first.

Brains seem to me like an organ ready made to tie itself in knots. My experience of dreams is that they very often represent a sort of feedback of built up energy from the day's stresses. As such they allow for the brain to untangle. The fact that an organism rests at all may be primarily due to an evolved need to flush the brain. Dreams are merely the inside out feedback of "charged" memory systems needing to be reset.

Another understanding I have developed of dreams is that they are experiences of the brain when the "flood" of neural-sensory input is switched off. Then the memory and the internal states of the brain become the main source of influence through feedback circuits on the sensory cortex.

 

[Nous]

Specifically looking for one frontal lobe species does not address the issue of the evolution of the brain and nervous system over billions of years.

I was only addressing the statement found in your post that "the basic neurophysiologic mechanisms supporting consciousness in humans are found at the earliest points of vertebrate brain evolution."

 

[sealchan]

I couldn't find anything much beyond looking at skull shapes.

I think that looking at sleep and dreams is being established here as a deeper insight than skull shapes. Maybe with this insight and a connection between dreams as an aspect of conscious neural systems, we might have scientists going back and looking more closely at reptilian brains to see if consciousness might be a feature of the mammal-reptilian last common ancestor. Finding some hard to visual distinguish frontal lobe for these species may become a "thing" at that point.

 

[Nous]

I couldn't find anything much beyond looking at skull shapes.

I think that looking at sleep and dreams is being established here as a deeper insight than skull shapes. Maybe with this insight and a connection between dreams as an aspect of conscious neural systems, we might have scientists going back and looking more closely at reptilian brains to see if consciousness might be a feature of the mammal-reptilian last common ancestor. Finding some hard to visual distinguish frontal lobe for these species may become a "thing" at that point.

So you can't find any evidence either that substantiates the claim that "the basic neurophysiologic mechanisms supporting consciousness in humans are found at the earliest points of vertebrate brain evolution."

 

[shunyadragon]

Again, in order to test a hypothesis about "degree" vs. "kind" with respect to "experience," one would need to define those terms. Right?



I don't know what you're trying to say here. The frontal lobe was not present at "the earliest point of vertebrate brain evolution," as far as I know.

Terms are clearly and specifically defined in the scientific references.

 

[shunyadragon]

So you can't find any evidence either that substantiates the claim that "the basic neurophysiologic mechanisms supporting consciousness in humans are found at the earliest points of vertebrate brain evolution."

Ignoring the scientific references provided, and there will be more. It is not a matter of 'finding' it is a matter of you reading and clearly understanding the references. You apparently did not read the whole reference. It is not necessarily specifically consciousness that is found. It is physical differentiation of the brain in the earlier stages of evolution that leads to more complex brains and consciousness.

 

[Nous]

Terms are clearly and specifically defined in the scientific references.

Quote the definitions and link to the studies that tested such hypothesis, please.

 

[Nous]

Ignoring the scientific references provided there will be more. It is not a matter of 'finding' it is a matter of you reading and clearly understanding the references. You apparently did not read the whole reference. It is not necessarily specifically consciousness that is found. It is physical differentiation of the brain in the earlier stages of evolution that leads to more complex brains and consciousness.

Cite the evidence that substantiates the claim that "the basic neurophysiologic mechanisms supporting consciousness in humans are found at the earliest points of vertebrate brain evolution."

 

[It Aint Necessarily So]

you have volumes of opinion , opinions that are short of observational facts.

You're writing to a community that has many individuals that interested and well educated in science. They have seen and evaluated the evidence. How much power of persuasion do you think somebody that is unaware of that evidence can have?

Did you read Salvador's post on Human Chromosome 2? I don't recall you responding to it. Were you aware of that smoking gun piece of information regarding ape evolution, which includes human evolution? Are you now aware of the evidence?

how can anybody verify evolution ?

It's been observed.

the hypothesis of evolution remains falsified

I assume that you meant falsifiable. I'm sure that you know that the theory (or hypothesis if you prefer) has never been falsified.

In short, as usual, materialism gets nowhere.

Unless you count the bounties of scientific inquiry, which is grounded in materialism, or more correctly, physicalism, since matter is just one manifestation of physical reality.

you materialists obviously aren't interested.

What do you have to offer that's useful and avoids materialism?

in order to test a hypothesis about "degree" vs. "kind" with respect to "experience," one would need to define those terms. Right?

There's no clear line between the two. Accumulated small changes in degree often result in the emergence of new kinds of things. We can say that gradual quantitative changes can eventually become qualitative differences. Acorns become oaks. As largely indeterminate subatomic particles accrue, largely deterministic objects result.

So how about degree referring to quantitative differences, and kind to qualitative ones, acknowledging that the line between them can be fuzzy. My dogs have some language skills. They understand about fifty words each, but can't speak or invent words. Is the difference between that and what human beings can do a matter of degree or kind? I'd say a little of each.