On Financing our ministry

How Is Our Ministry Financed?:
Each year, we print and distribute hundreds of millions of Bibles and pieces of Bible literature. We build and operate branch offices and printeries around the world. Tens of thousands of congregations meet in modest yet attractive places of worship called Kingdom Halls. Who pays for all of this?

Our work is supported entirely by voluntary donations. (2 Corinthians 9:7) In 1879, the second issue of this magazine stated: “‘Zion’s Watch Tower’ [as this magazine was then called] has, we believe JEHOVAH for its backer, and while this is the case it will never beg nor petition men for support.” We have not wavered from that policy.


Donations are sent directly to one of our branch offices or placed in a contribution box that is located in each Kingdom Hall. But we never tithe, take up collections, or charge a fee for our services or publications. We are not paid to preach, to teach in the congregation, or to help build places of worship. After all, Jesus said: “You received free, give free.” (Matthew 10:8) All ministers at our branch offices and at our world headquarters, including those making up the Governing Body of Jehovah’s Witnesses, are unsalaried members of a religious order.

                                                                             “As is the case with all the activities of Jehovah’s Witnesses, religious funding is handled on a voluntary basis, each one personally determining the amount and frequency of his religious ‘donations.’”—European Court of Human Rights, 2011

Donated funds are also used for disaster relief. The early Christians were pleased to share in relief measures for victims of adversity. (Romans 15:26) We likewise assist the afflicted by rebuilding their homes and places of worship and by providing food, clothing, and medical treatment.

File under 'Well said' X

"Nearly all men can stand adversity, but if you want to test a man's character, give him power."
Abraham Lincoln

Psalms15-21 New Jerusalem Bible

15)1 [Psalm Of David] Yahweh, who can find a home in your tent, who can dwell on your holy mountain?

2 Whoever lives blamelessly, who acts uprightly, who speaks the truth from the heart,

3 who keeps the tongue under control, who does not wrong a comrade, who casts no discredit on a neighbour,

4 who looks with scorn on the vile, but honours those who fear Yahweh, who stands by an oath at any cost,

5 who asks no interest on loans, who takes no bribe to harm the innocent. No one who so acts can ever be shaken.
16)1 [In a quiet voice Of David] Protect me, O God, in you is my refuge.

2 To Yahweh I say, 'You are my Lord, my happiness is in none

3 of the sacred spirits of the earth.' They only take advantage of all who love them.

4 People flock to their teeming idols. Never shall I pour libations to them! Never take their names on my lips.

5 My birthright, my cup is Yahweh; you, you alone, hold my lot secure.

6 The measuring-line marks out for me a delightful place, my birthright is all I could wish.

7 I bless Yahweh who is my counsellor, even at night my heart instructs me.

8 I keep Yahweh before me always, for with him at my right hand, nothing can shake me.

9 So my heart rejoices, my soul delights, my body too will rest secure,

10 for you will not abandon me to Sheol, you cannot allow your faithful servant to see the abyss.

11 You will teach me the path of life, unbounded joy in your presence, at your right hand delight for ever.
17)1 [Prayer Of David] Listen, Yahweh, to an upright cause, pay attention to my cry, lend an ear to my prayer, my lips free from deceit.

2 From your presence will issue my vindication, your eyes fixed on what is right.

3 You probe my heart, examine me at night, you test me by fire and find no evil. I have not sinned with my mouth

4 as most people do. I have treasured the word from your lips,

5 my steps never stray from the paths you lay down, from your tracks; so my feet never stumble.

6 I call upon you, God, for you answer me; turn your ear to me, hear what I say.

7 Show the evidence of your faithful love, saviour of those who hope in your strength against attack.

8 Guard me as the pupil of an eye, shelter me in the shadow of your wings

9 from the presence of the wicked who would maltreat me; deadly enemies are closing in on me.

10 Engrossed in themselves they are mouthing arrogant words.

11 They are advancing against me, now they are closing in, watching for the chance to hurl me to the ground,

12 like a lion preparing to pounce, like a young lion crouching in ambush.

13 Arise, Yahweh, confront him and bring him down, with your sword save my life from the wicked,

14 Yahweh, from mortals, by your hand, from mortals whose part in life is in this world. You fill their bellies from your store, their children will have all they desire, and leave their surplus to their children.

15 But I in my uprightness will see your face, and when I awake I shall be filled with the vision of you.
18)1 [For the choirmaster Of David, the servant of Yahweh, who addressed the words of this song to Yahweh when Yahweh had delivered him from all his enemies and from the clutches of Saul. He said:] I love you, Yahweh, my strength (my Saviour, you have saved me from violence).

2 Yahweh is my rock and my fortress, my deliverer is my God. I take refuge in him, my rock, my shield, my saving strength, my stronghold, my place of refuge.

3 I call to Yahweh who is worthy of praise, and I am saved from my foes.

4 With Death's breakers closing in on me, Belial's torrents ready to swallow me,

5 Sheol's snares every side of me, Death's traps lying ahead of me,

6 I called to Yahweh in my anguish, I cried for help to my God; from his Temple he heard my voice, my cry came to his ears.

7 Then the earth quaked and rocked, the mountains' foundations shuddered, they quaked at his blazing anger.

8 Smoke rose from his nostrils, from his mouth devouring fire (coals were kindled at it).

9 He parted the heavens and came down, a storm-cloud underneath his feet;

10 riding one of the winged creatures, he flew, soaring on the wings of the wind.

11 His covering he made the darkness, his pavilion dark waters and dense cloud.

12 A brightness lit up before him, hail and blazing fire.

13 Yahweh thundered from the heavens, the Most High made his voice heard.

14 He shot his arrows and scattered them, he hurled his lightning and routed them.

15 The very springs of ocean were exposed, the world's foundations were laid bare, at your roaring, Yahweh, at the blast of breath from your nostrils!

16 He reached down from on high, snatched me up, pulled me from the watery depths,

17 rescued me from my mighty foe, from my enemies who were stronger than I.

18 They assailed me on my day of disaster but Yahweh was there to support me;

19 he freed me, set me at large, he rescued me because he loves me.

20 Yahweh rewards me for my uprightness, as my hands are pure, so he repays me,

21 since I have kept the ways of Yahweh, and not fallen away from my God.

22 His judgements are all before me, his statutes I have not put away from me.

23 I am blameless before him, I keep myself clear of evil.

24 So Yahweh repaid me for acting uprightly because he could see I was pure.

25 You are faithful to the faithful, blameless with the blameless,

26 sincere to the sincere, but cunning to the crafty,

27 you save a people that is humble and humiliate those with haughty looks.

28 Yahweh, you yourself are my lamp, my God lights up my darkness;

29 with you I storm the rampart, with my God I can scale any wall.

30 This God, his way is blameless; the word of Yahweh is refined in the furnace, for he alone is the shield of all who take refuge in him.

31 For who is God but Yahweh, who is a rock but our God?

32 This God who girds me with strength, who makes my way free from blame,

33 who makes me as swift as a deer and sets me firmly on the heights,

34 who trains my hands for battle, my arms to bend a bow of bronze.

35 You give me your invincible shield (your right hand upholds me) you never cease to listen to me,

36 you give me the strides of a giant, give me ankles that never weaken.

37 I pursue my enemies and overtake them, not turning back till they are annihilated;

38 I strike them down and they cannot rise, they fall, they are under my feet.

39 You have girded me with strength for the fight, bent down my assailants beneath me,

40 made my enemies retreat before me; and those who hate me I destroy.

41 They cry out, there is no one to save; to Yahweh, but no answer comes.

42 I crumble them like dust before the wind, trample them like the mud of the streets.

43 You free me from the quarrels of my people, you place me at the head of the nations, a people I did not know are now my servants;

44 foreigners come wooing my favour, no sooner do they hear than they obey me;

45 foreigners grow faint of heart, they come trembling out of their fastnesses.

46 Life to Yahweh! Blessed be my rock! Exalted be the God of my salvation,

47 the God who gives me vengeance, and subjects whole peoples to me,

48 who rescues me from my raging enemies. You lift me high above those who attack me, you deliver me from the man of violence.

49 For this I will praise you, Yahweh, among the nations, and sing praise to your name.

50 He saves his king time after time, displays his faithful love for his anointed, for David and his heirs for ever.
19)1 [For the choirmaster Psalm Of David] The heavens declare the glory of God, the vault of heaven proclaims his handiwork,

2 day discourses of it to day, night to night hands on the knowledge.

3 No utterance at all, no speech, not a sound to be heard,

4 but from the entire earth the design stands out, this message reaches the whole world. High above, he pitched a tent for the sun,

5 who comes forth from his pavilion like a bridegroom, delights like a champion in the course to be run.

6 Rising on the one horizon he runs his circuit to the other, and nothing can escape his heat.

7 The Law of Yahweh is perfect, refreshment to the soul; the decree of Yahweh is trustworthy, wisdom for the simple.

8 The precepts of Yahweh are honest, joy for the heart; the commandment of Yahweh is pure, light for the eyes.

9 The fear of Yahweh is pure, lasting for ever; the judgements of Yahweh are true, upright, every one,

10 more desirable than gold, even than the finest gold; his words are sweeter than honey, that drips from the comb.

11 Thus your servant is formed by them; observing them brings great reward.

12 But who can detect his own failings? Wash away my hidden faults.

13 And from pride preserve your servant, never let it be my master. So shall I be above reproach, free from grave sin.

14 May the words of my mouth always find favour, and the whispering of my heart, in your presence, Yahweh, my rock, my redeemer.
20)1 [For the choirmaster Psalm Of David] May Yahweh answer you in time of trouble, may the name of the God of Jacob protect you!

2 May he send you help from the sanctuary, give you support from Zion!

3 May he remember all your sacrifices and delight in your burnt offerings! Pause

4 May he grant you your heart's desire and crown all your plans with success!

5 So that with joy we can hail your victory and draw up our ranks in the name of our God. May Yahweh grant all your petitions.

6 Now I know that Yahweh gives victory to his anointed. He will respond from his holy heavens with great deeds of victory from his right hand.

7 Some call on chariots, some on horses, but we on the name of Yahweh our God.

8 They will crumple and fall, while we stand upright and firm.

9 Yahweh, save the king, answer us when we call.
21)1 [For the choirmaster Psalm Of David] Yahweh, the king rejoices in your power; How your saving help fills him with joy!

2 You have granted him his heart's desire, not denied him the prayer of his lips.Pause

3 For you come to meet him with blessings of prosperity, put a crown of pure gold on his head.

4 He has asked for life, you have given it him, length of days for ever and ever.

5 Great his glory through your saving help; you invest him with splendour and majesty.

6 You confer on him everlasting blessings, you gladden him with the joy of your presence.

7 For the king puts his trust in Yahweh; the faithful love of the Most High will keep him from falling.

8 Your hand will reach all your enemies, your right hand all who hate you.

9 You will hurl them into a blazing furnace on the day when you appear; Yahweh will engulf them in his anger, and fire will devour them.

10 You will purge the earth of their descendants, the human race of their posterity.

11 They have devised evil against you but, plot as they may, they will not succeed,

12 since you will make them turn tail, by shooting your arrows in their faces.

13 Rise, Yahweh, in your power! We will sing and make music in honour of your strength.

Separating science from scientism.

Rules for Discounting Scientific Pretensions

Evolution News & Views November 27, 2013 5:04 AM

An unusual article appeared recently in Nature. Three scientists -- a biologist, a mathematician, and a biosecurity expert -- offered twenty reasons why politicians should be wary of scientific claims.

William J. Sutherland, David Spiegelhalter and Mark A. Burgman, in "Policy: Twenty tips for interpreting scientific claims," acknowledged that scientists are often too busy to get involved in politics. Politicians, on the other hand, are usually too busy to learn the evidence and methods behind the claims of scientists. Yet the decisions politicians make often affect science. How can scientists help them make more informed decisions?

In this context, we suggest that the immediate priority is toimprove policy-makers' understanding of the imperfect nature of science. The essential skills are to be able to intelligently interrogate experts and advisers, and to understand the quality, limitations and biases of evidence.We term these interpretive scientific skills. These skills are more accessible than those required to understand the fundamental science itself, and can form part of the broad skill set of most politicians. (Emphasis added.)

Realizing that "others will have slightly different lists," they offered their twenty best tips for politicians. We won't list all of them, but some have relevance to the debate on origins. Skipping the ones dealing with lab technique, error rates and significance tests, let's look at a few that are important for evaluating Darwinian claims and considering the validity of intelligent design.

3. Bias is rife. "Confirmation bias arises when scientists find evidence for a favored theory and then become insufficiently critical of their own results, or cease searching for contrary evidence," they say, providing examples. Do we not see Darwinists doing this all the time? Because they approach data with the presumption that Darwinian theory is a fact, every observation becomes a confirmation of Darwinism, no matter how counter-intuitive.

5. Correlation does not imply causation. One commenter recalled the old chestnut that a rooster always crows before sunrise, therefore the rooster causes the sunrise. The authors point out that coincidence or hidden variables can be responsible for a pattern. We've seen origin-of-life researchers conclude that a change in oxygen levels allowed life to emerge, or that some catastrophe cleared the way for a rapid diversification of life in the Cambrian explosion.

7. Extrapolation beyond the data is risky. "Patterns found within a given range do not necessarily apply outside that range." Darwinians are notorious extrapolators. They will stretch an inch into a mile: extrapolating millimeter-size changes in finch beaks into the origin of finches, or hardly-observable differences in cichlid fish as vindication of Darwin's theory of universal common descent. All macroevolutionary claims are extrapolations of microevolutionary changes.

9. Controls are important. As a historical investigation, Darwinism is essentially an uncontrolled science. There's only been one history of the world. We can't replay the tape of evolution to see what would happen a second time, let alone provide two worlds, one unconstrained and the other using a placebo of some sort. The same complaint might be made against intelligent design; in that case, though, we have many examples of how intelligent agents work.

12. Scientists are human. This truism bears quoting the authors' elaboration:

Scientists have a vested interest in promoting their work, often for status and further research funding, although sometimes for direct financial gain. This can lead to selective reporting of results and occasionally, exaggeration. Peer review is not infallible: journal editors might favor positive findings and newsworthiness. Multiple, independent sources of evidence and replication are much more convincing.

16. Study relevance limits generalizations. "The relevance of a study depends on how much the conditions under which it is done resemble the conditions of the issue under consideration." Intelligent design advocates need to establish the resemblance of biological codes to human-generated codes, not assume it. Darwinists, on the other hand, need to show how "evolutionary algorithms" relate to the origin of life or to natural selection, when the latter have no guiding hand selecting the target and ensuring a desired outcome.

19. Data can be dredged or cherry-picked. "Evidence can be arranged to support one point of view." In a sense, any argument arranges evidence to support a viewpoint. A good argument, though, takes due consideration of all contrary evidence and alternative explanations. That's what Stephen Meyer did in his books Signature in the Cell andDarwin's Doubt; though defending the case for intelligent design, he exercised diligence to fairly consider all the leading arguments against it. Darwinians, by contrast, mention intelligent design only in the context of snarky insults or misrepresentations when not ignoring it altogether.

Sutherland, Spiegelhalter and Burgman are to be commended for bringing this reality check to readers of Nature. Their list is far from exhaustive; about ten more were added by readers in the comments. One reader said that this list did not "weight" each entry in a practical way to render it useful for measurement. Additionally, an introductory course in philosophy of science could expand the list substantially. Even basic questions such as the definition of science, demarcation criteria between science and pseudoscience, the nature of evidence, the validity of induction, and the role of explanation prove to be highly inscrutable.

With this partial list, though, we can see useful ways to scrutinize evolutionary claims, and to render research into intelligent design more robust. One hopes the article makes the rounds and helps policy makers and politicians -- not least school board members -- improve their interpretive skills when confronted with the all-too-common bombastic slogans, "Scientists now know," and "All scientists believe."

Family resemblance?

Why We Don't Look Like Chimps

Ann Gauger October 2, 2015 3:30 AM

Pictures showing the gradual transition of an ape-like creature to a human one are part of the cultural Gestalt. They are so ubiquitous that people use the idea for jokes. You've probably seen the picture describing the evolution of man from a bent-over ape to a bent-over office worker on the computer. But do such pictures represent the truth about our history?

Let's consider just one part of the transition that would be required -- to go from an ape-like face to a human one. The portraits of our supposed ancestors are in museums everywhere, and on the web pages ofNational Geographic -- the latest one, H. naledi, can be found there now. But whether or not that reconstructed face is a part of our history, the question remains: Is there enough time for us to have acquired by purely, Darwinian natural processes the differences that make us look human as opposed to ape-like?

A recent paper purports to tell us how it happened, at least from a genetic perspective. Prescott et al. report the regulatory changes that might have caused the change in morphology (the overall shape) of our faces. On the whole it's an interesting paper with a lot of hard work involved.

The title, "Enhancer Divergence and cis-Regulatory Evolution in the Human and Chimp Neural Crest," may sound a little cryptic to the uninitiated. Let me provide some background and define some terms. Enhancers are regulatory sequences found in the DNA near the gene(s) they regulate. They act by "enhancing" the expression of those nearby genes. They are also called cis-regulatory elements, hence the "Enhancer Divergence and cis-Regulatory Evolution" part of the title.

Neural crest cells come from a particular part of the early-developing brain, and they migrate out into the embryo to form the face and other structures in the body. Thus they have a major role to play in embryonic development of the face. Mutations that affect neural crest cells can cause major cranio-facial abnormalities.

The popular model is that changing enhancers is the way new morphological features evolved, changes such as from an ape-like face to a human one.

Now for the paper. Prescott et al. began by inducing stem cells of both chimp and human lineages to develop into neural crest cells. (They mostly used in vitro pluripotent stems cells (IPSCs), which are not of embryonic origin. Unfortunately, they did use some human embryo-derived cells to verify that their IPSCs were behaving normally.) From the IPSCs they identified enhancer-like sequences specific to neural crest cells. They then checked for patterns of gene expression driven by those enhancers that differed between chimp and human cells. Having identified those, they then used several methods to examine whether those enhancers did in fact act in a species-specific way in the neural crest. They also checked whether or not the genes they had identified caused human cranio-facial abnormalities when mutated. Some did.

Essentially, they looked for differences between humans and chimps in their enhancer sequences upstream of genes involved in neural crest development, and found them.

How convinced am I that their results are valid? They say they identified at least 208 enhancers that work together cooperatively to regulate neural crest gene expression. That I accept, though some of the details may be wrong. 208 is a reasonable number of enhancers to be involved in neural crest specification and behavior. They say that there are probably other enhancers they didn't identify, and the enhancers they did identify will no doubt have effects in other tissues. Fine. They also report having found multiple enhancer elements upstream of the same gene, each with a positive or negative effect on gene expression that work together. None of this is a surprise -- it confirms the idea that gene regulatory networks are complex and cooperative, and that changing nucleotides in an enhancer (a cis-regulatory element) can change its effect on nearby genes.

My difficulty is with their claim that anything like this evolved. There is plenty of use of the word evolution in the introduction and discussion sections of this paper. It's actually not surprising that they use evolution so often as an explanatory concept. Evolution is the dominant explanation right now for how things got to be the way they are, so of course these differences in enhancer sequences are explained by evolution...right?

Let's check the logic. Premise: evolution happens by changing enhancer sequences in a species-specific way. Observation: there are species-specific differences in enhancers. Conclusion: evolution is responsible for these species-specific changes.

See the problem? That's called circular reasoning. If you accept the premise, then the conclusion is automatic because the two statements are actually saying the same thing. If you don't accept the premise, of course, you will be unconvinced by this argument. Thus the paper assumes Darwinian evolution without demonstrating that it had anything to do with it.

So let's ask the question. Could naturalistic processes guided only by natural selection have accomplished any of this? Changes to the expression of one gene or another can affect morphology -- changing the expression of the gene ALX1 affects the size and shape of finch beaks, for example. Getting one regulatory change to an enhancer is notimpossible. But there are multiple enhancers controlling multiple genes involved in facial morphology (see the paper in Nature by Lamichhaneyet al.), and to get coordinated regulation of multiple genes, multipleenhancers must have changed in a coordinated fashion.

Is that possible? Durrett and Schmidt published a paper examining how long it would take to have two coordinated mutations (one inactivating and the other activating) take place in an evolving hominin population. They found it would require in excess of 100 million years. Obviously, the hominin population did not have that long to wait for regulatory change. We supposedly diverged from chimps six million years ago.

Nowhere in this paper is it demonstrated that anything like this regulatory network could have evolved step by step in the time available. All it establishes is that our faces are different from chimps because we have different regulatory sequences. In fact, I don't know of anywhere it has been demonstrated that regulatory changes on this scale could bethe product of evolution.

In the meantime, we do know something that can coordinate change on this scale. It's called intelligence.

Darwinists continue to major in minors.

Rapid" Evolution Observed in Guppies? As Always, It Depends on What You Mean by Evolution

David Klinghoffer October 1, 2015 3:31 PM 

Reporting in Proceedings of the Royal Society B, researchers have rigorously demonstrated something totally unsurprising -- only to turn around and offer it as evidence for something quite different and quite surprising. The technical term for that is bait-and-switch.

A team showed that if you take guppies and move them from an environment rich in predators to one that's largely predator-free, this can have an effect on a superficial trait like coloration. Who would have thought otherwise? Given (a) characteristics that vary from generation to generation, (b) heritability, and (c) an environment or other factors that favor one over another, it would be startling if selection didn't result in small-scale change over time, even over rather short periods -- microevolution, in other words, at its finest.

From the Abstract ("Selection analysis on the rapid evolution of a secondary sexual trait"):

Here, we present a study of experimental evolution of male colour in Trinidadian guppies where we tracked both evolutionary change and individual-based measures of selection. Guppies were translocated from a predator-rich to a low-predation environment within the same stream system. We used a combination of common garden experiments and monthly sampling of individuals to measure the phenotypic and genetic divergence of male coloration between ancestral and derived fish. Results show rapid evolutionary increases in orange coloration in both populations (1 year or three generations), replicating the results of previous studies. Unlike previous studies, we linked this evolution to an individual-based analysis of selection. By quantifying individual reproductive success and survival, we show, for the first time, that males with more orange and black pigment have higher reproductive success, but males with more black pigment also have higher risk of mortality. The net effect of selection is thus an advantage of orange but not black coloration, as reflected in the evolutionary response. This highlights the importance of considering all components of fitness when understanding the evolution of sexually selected traits in the wild.

Commenting in Science Daily ("Evolution shown in real time"), an author of the study, UC Riverside biologist David Reznick, points out the relevance to the evolution debate as he sees it:

"People think of evolution as historical. They don't think of it as something that's happening under our nose. It is a contemporary process. People are skeptical; they don't believe in evolution because they can't see it. Here, we see it. We can see if something makes you better able to make babies and live longer," Reznick said. [Emphasis added.]

But the kind of evolution Dr. Reznick and his colleagues observed is not the same thing -- unguided macroevolution, novel biological information fortuitously generating new animals -- that is subject to skepticism by those who "don't believe in evolution because they can't see it." Set aside the gratuitous swipe at skeptics. Show me the most devout creationist and I will show you someone perfectly happy to accept every word of David Reznick's results, and completely untroubled by them.

Don't Darwinists know this? I understand wanting to draw attention to your work by highlighting how it casts light on a hot debate. But first find out what both sides in the debate say, what they're arguing about, andthen tell us how your work ought to figure into the discussion.

Darwinism Vs. the real world XIV

Blood Pressure: Standing Up to Gravity

Howard Glicksman October 1, 2015 3:34 AM

Editor's note: Physicians have a special place among the thinkers who have elaborated the argument for intelligent design. Perhaps that's because, more than evolutionary biologists, they are familiar with the challenges of maintaining a functioning complex system, the human body. With that in mind, Evolution News & Views is delighted to present this series, "The Designed Body." Dr. Glicksman practices palliative medicine for a hospice organization.

The cardiovascular system's job is to provide the cells of the body with what they need to live, grow, and work properly by providing enough blood flow to the tissues. To do this, the heart must pump well enough, there must be enough blood in the arteries, and the arterioles must limit how much blood enters the tissues by applying peripheral vascular resistance. It is these three factors that mainly determine the arterial blood pressure.

But life is a dynamic process, and changes in fluid balance, body position, and physical activity require that each of these factors be constantly adjusted to keep the blood pressure where it needs to be to survive. Just as a car's ability to perform well enough goes above and beyond its mere blueprints, so too, the ability of the body to survive within the laws of nature goes above and beyond its mere DNA.

Anyone who has ever felt dizzy upon standing up knows this to be true. When it comes to being able to stand up to gravity, the numbers regarding blood pressure have to be just right or else we'll find ourselves lying on the ground. Just imagine our ancient ancestors trying to survive if their body couldn't control their blood pressure so as to remain in the upright position for an extended period. Evolutionary biologists seem to forget that explaining how life came about requires showing, not just how it looks, but also how it must work within the laws of nature to survive.

It's important to remember that, barring a local obstruction from a clot, or a hemorrhage from an injury, the blood pressure provides the force resulting in adequate blood flow to the tissues of the body. The blood pressure fluctuates between the diastolic (DP) and the systolic pressure (SP) but it is the mean arterial blood pressure (MAP) that is used when considering blood flow. As noted previously, since systole takes up one third of the cardiac cycle and diastole, two thirds, the MAP can be calculated as 1/3 SP + 2/3 DP. An MAP of 100 mmHg could come from a BP of 150/75 or 120/90 and a BP of 90/60 would give an MAP of 70 mmHg.

Since gravity pulls blood down, when the body is upright the MAP in the brachial artery is higher than the one in the arteries leading to the brain. Because the gravitational constant and the distance between the heart and the head are constant, the MAP in the brain, compared to the one in the aorta and in the brachial artery, can be determined.

At rest, the MAP in the aorta, as the blood exits the left ventricle, is usually about 80-110 mmHg. By the time the blood travels to the arms it has lost some energy and the MAP has dropped to 70-100 mmHg. Due the additional effect of gravity, when the body is in the upright position, the MAP in the brain drops to about 60-75 mmHg. Since it is the blood pressure that generates blood flow, this means that, in general, the lower the MAP in a given organ the lower the blood flow.

When you are sitting or standing, the force moving blood to your hands is higher than the one moving blood to your brain. However, despite this relatively low pressure, the brain has a mechanism in place, calledautoregulation, to help ensure adequate blood flow so its metabolic needs can be met.

Autoregulation within a given organ usually takes place independent of nervous or hormonal control and allows for adequate blood flow. It is important to understand that the blood flow (Q) within a given organ is directly related to its MAP (P) and inversely related to the vascular resistance in its arterioles (R). The higher the pressure, the more blood flow and the lower the pressure, the less blood flow. And the higher the arteriolar resistance within a given organ, the less blood flow, and the lower the arteriolar resistance, the more blood flow.

This natural law can be expressed as Q = P/R. One can therefore see that if the MAP drops in the brain, it can try to compensate by reducing its vascular resistance at the same time so it can maintain adequate blood flow to meet its metabolic needs. This is particularly important for brain function because of its high metabolic rate and extreme sensitivity to changes in blood flow.

Vascular resistance is directly related to the degree of muscle contraction around the arterioles.

More contraction causes more resistance and less contraction causes less resistance. When the MAP drops in the brain, autoregulation makes the vascular resistance drop almost immediately by relaxing the arteriolar muscles, increasing blood flow back to where it is supposed to be.

But, like everything else in life, autoregulation and its ability to control the blood flow in the brain does have objective limits. Regarding significant drops in blood pressure, there is only so much relaxation of the arteriolar muscles and reduction in vascular resistance that can take place.

Wince life is a dynamic process where the blood pressure is always fluctuating due to various circumstances, the body has to always keep it under control to prevent brain malfunction.

When you stand up, not only does gravity prevent blood from traveling to the brain, it also makes about 500 mL move from the veins in your chest and abdomen into your legs. This sudden drop in the volume of blood returning to the heart through the veins usually causes a

40 percent drop in the cardiac output and with it, a further drop in the MAP in the brain. So much so that autoregulation is incapable of adequately compensating for this sudden drop in pressure causing reduced blood flow. When this happens, we feel light-headed. If our body doesn't correct the situation or we don't get our head below our heart fast enough, we may pass out.

To fix this problem quickly, so we can remain standing, the body must know that if

Q = P/R, then P = Q x R. This expresses what has already been explained above. The blood pressure (P) is directly related to the total blood flow in the circulation (Q) (which is determined by how well the heart pumps and how much blood is in the arteries) and the peripheral vascular resistance (R). To prevent passing out on suddenly standing up, the body must immediately increase the cardiac output and the peripheral vascular resistance as well.

When it comes to making quick adjustments to blood pressure, it is the sympathetic nervous system, in response to the data it receives from the baroreceptors in main arteries carrying blood to the brain, that acts to solve the problem. When the MAP in the major arteries is in the normal range (70-100 mmHg), the frequency of impulses from the baroreceptors to the brain remains relatively stable. However, as the MAP deviates up or down from normal, the increase or decrease in the stretching of the vessel wall makes the baroreceptors increase or decrease the frequency of their messages. In response, the brain stem stimulates the sympathetic nervous system in an inverse pattern.

An increase in the MAP causes an increase in the frequency of impulses from the baroreceptors and a decrease in sympathetic activity. And a decrease in the MAP (like from standing up too quickly) causes a decrease in the frequency of impulses from the baroreceptors and an increase in sympathetic activity.

When we stand up too quickly, causing the MAP in our brachial artery to drop below 70 mmHg and the MAP in our brain to drop below 50 mmHg, we feel dizzy. By attaching to specific receptors, the increased output of sympathetic neurohormones quickly makes the systemic veins send more blood back into the arteries and the heart pump harder and faster. These quick actions combine to immediately increase the cardiac output (Q). And, increased sympathetic activity makes the muscles surrounding the arterioles in most of the tissues of the body contract more, quickly increasing the peripheral vascular resistance (R) as well.

As noted above, P = Q x R, so this rapid increase in Q and R, brings the MAP in the brain back to a level that allows its autoregulatory mechanism to maintain adequate blood flow. We experience this by our dizziness resolving within a second or two and being able to carry on. So it looks like the system the body uses to control its blood pressure to stand up to gravity seems to know what it's doing.

What has been described here is the real situation that faces human life. Not only must it know how the laws of nature work and have the mechanisms in place to deal with them, it must also do the right thing at exactly the right moment and do it well enough to survive.

By only describing how life looks, and not how it actually works, evolutionary biologists claim to have shown how life came into being by chance and the laws of nature alone. This means that all of the control mechanisms needed for all the chemical and physiological parameters to support life must have come about the same way.

Moreover, it is interesting to consider that in the last century, by using their intellectual powers to measure these parameters and sometimes do something about them, medical scientists have only recently been able to do what the body has had to do, by necessity, since the very beginning of its existence. For, as the next two articles in this series will demonstrate, when circumstances arise to overwhelm the body's ability to keep its blood pressure where it needs to be, real numbers matter.

Why sex fails as an engine for Darwinian evolution.

Can Sex Explain Evolution?

Denyse O'Leary September 29, 2015 3:54 AM 

Last time out, we looked at Darwin's theory of natural selection, alleged by some to be the single best idea anyone ever invented. The mere process of eliminating unfit examples of a type in a given environment builds up information over time, resulting in huge new layers of complexity.

But if no one can say what is fit or unfit according to natural selection, because nature has no direction, why must we pay attention to claims about natural selection? Why is there supposed to be anything to know?

Then there is Darwin's theory ofsexual selection, with its famous exemplar: the peacock's tail. An illustration may help us see why reasonable persons continue to doubt.

Picture a triplex: Tom, a world class cribbage addict in Apartment A, does no work and has no money (apart from social assistance and charity). Dick, in Apartment B, works eight shifts a week in trucking, so has no trouble paying his bills. Harry, formerly in Apartment C, went off and became a multimillionaire (legally) in packaging and shipping for the software industry.

Does work alone explain Harry's success? Did he work a thousand times harder and more often than Dick? Is that even possible? Or is it all an accident of fate, such that Tom or Dick might have stumbled down the same way and done the same thing?

Most human beings tend to doubt that it is so simple. Also, there are not a billion generations between Tom, Dick, and Harry. Not even one, actually.

And if each of these guys somehow ends up with fertile heirs, is any of them "unfit"?

Very well, so let us now look at Darwin's other theory, sexual selection:

Reproduction is expensive and can exert an additional evolutionary pressure. Darwin defined this pressure as sexual selection. Sexual selection operates through some members of a species having an advantage over others in terms of mating. It is the selection for traits that are solely concerned with increasing the mating success of an individual.

So fitter animals pass on their genes more frequently, so we don't know anything except that they do pass them on.

Traditionally, that has often been interpreted as, a more combative male wins more mates and sires more offspring, furthering evolution via his genes.

From a common sense perspective, there is a problem with the underlying assumption: The combative male may get himself seriously injured and be unable to protect his offspring. He may also be susceptible to a serious Y-linked disease to which the vanquished males are immune. So it is unclear whether fitter offspring reliably result from success in sexual competition.

Incidentally, human breeding is not a good analogy because breeders are "designers" who avoid breeding aggressive animals or those with serious genetic disease in their pedigree.

After a fruit fly experiment, some researchers offered an additional reason why sexual dominance does not necessarily speed evolution:

Females are frequently harassed and harmed by males attempting to obtain matings. When these males are also "choosy" with their courtship, there may be negative consequences to the species' ability to adaptively evolve.

Similarly, another study revealed many secrets of the convoluted sex lives of crickets, including the fact that "dominant males had fewer mates than subordinate males, but they had similar numbers of offspring."

Recently, a key sexual selection theory, Bateman's theory that promiscuity benefits males but not females, was subjected to replication studies (repeating the experiment to see if it works out) and it didn't replicate.

Sexual selection, despite its immense cultural popularity as an idea, does not seem to work as a mechanism for major evolutionary changes.

We are still stuck for a mechanism that replaces intelligence.