Editorial 1 : Glimpses of LUCA, the life-form from which all other life descended
Introduction
The origin of life on earth is one of the world’s most enduring mysteries. There are a number of competing theories, but all of them lack conclusive proof. Nonetheless, scientists widely believe a combination of geological, climatic, and chemical processes gave rise to the building blocks of life.
Origin theories
- In the 1920s, Alexander Oparin and J. B. S. Haldane independently proposed their origin theories — the first of their kind.
- In 1924 and 1929, Oparin and Haldane, respectively, suggested the first molecules making up the earliest life forms gradually self-organised from a “primordial soup” in a young earth’s tempestuous, prebiotic environment. This idea is today called the Oparin-Haldane hypothesis.
- Researchers have also conducted biochemistry experiments and found evidence to support this hypothesis.
- A particularly famous one was the Miller-Urey experiment in 1952, in which University of Chicago researchers Stanley Miller and Harold Urey showed that in the right conditions, inorganic compounds could give rise to complex organic compounds.
- Miller and Urey mixed methane, ammonia, and water, and when they applied a strong electric current — like a lightning strike might have — the mixture contained amino acids, the building blocks of proteins. They reported their discovery the very next year in the journal Science.
- While we have evidence today that the earth’s environment then may not have been much like what the experiment presumed to mimic, the very fact that amino acids could be created in a broth of inorganic molecules was groundbreaking.
- Other researchers have proposed other theories about the origin of life. A particularly prominent one is that meteorites from space could have brought the building blocks of life, sustained by discoveries on the earth as well as out there.
- In August 2019, French and Italian scientists reported discovering extra-terrestrial organic material 3.3 billion years old, whereas Japan’s Hayabusa 2 mission to the asteroid Ryugu indicated the presence of more than 20 amino acids there.
LUCA and the molecular clock
- As mysteries go, a close second to the origin of life is how life-forms evolved to produce the rich diversity we see around us today.
- Researchers believe all three branches of life — bacteria, archaea, and eukarya — originated from a single cell, called the last universal common ancestor (LUCA).
- There is no fossil evidence to support the existence of LUCA, but the fact that modern genomes share so many features provides some insights.
- An important concept that allows scientists to reconstruct the ‘tree of life’ is the theory of the molecular clock.
- According to a simplified version of the theory, the rate at which mutations are added or removed from a population’s genome is proportional to the rate of acquiring new mutations, which is constant.
- To calibrate the molecular clock to a particular rate of mutations, researchers establish links between a genome and known events, such as the ‘date’ on which the first mammal evolved or the age of certain fossils. These links act like temporal benchmarks.
- Thanks to the large number of genome sequences and fossils of various organisms, as well as the computing power available today, researchers routinely use the molecular clock to understand the evolution of various life-forms on earth through time.
Which is older: LUCA or fossils?
- In a recent paper researchers constructed a phylogenetic tree of 350 bacterial and 350 archaeal genomes.
- Then, using a molecular clock, the team estimated when LUCA could have originated: around 4.2billion years ago, just 300 million years after the earth itself formed.
- The team also reported that LUCA may have had a small genome, of some 2.5 million bases and encoding around 2,600 proteins, all just enough to help it survive in a unique environmental niche.
- The team also suggested the metabolites produced by LUCA — compounds produced as a result of its metabolism — could have created a ‘secondary’ ecosystem in which other microbes could have emerged.
- Importantly, the origin of LUCA by 4.2 billion years significantly predates previous suggestions about the origin of life on earth.
- For context, researchers have found fossil records of the earliest life-forms in the Pilbara Craton in western Australia, one of the few places on the planet where archaean rocks are exposed aboveground and accessible.
- Studies of these fossils have suggested that life that lived on the rocks emerged around 3.4 billion years ago. The current study, on the other hand, pushes this date back by almost a billion years, almost on the heels of the birth of our planet itself.
- The researchers also found some reasons to believe LUCA may have had genes responsible for immunity, suggesting it had to fight off viruses.
Conclusion
The insights into evolution they provide will also give a significant fillip to human ambitions to engineer synthetic organisms for various industrial, chemical, and biological processes on the earth, as well as to create or moderate ecosystems on other planets in the future.
Editorial 2 : The problem with billionaire consumption
Context
The lavish and extended wedding celebrations of billionaire Mukesh Ambani’s youngest son has brought to the forefront the question of “conspicuous consumption” of the rich.
Perspectives from the right and left
- A defence of billionaires’ consumption would run as follows: in a liberal capitalist democracy, there are no restrictions on what one chooses to do with one’s private property.
- Assuming that market processes are fair, billionaires’ consumption expenditure — no matter how lavish — is a legitimate exercise of their private freedoms and cannot be faulted.
- The existence of inequality is not their concern, but the manifestation of flawed policy that restricts market freedom and curtails pure competition.
- Increasing market access, in this view, would ensure that everyone has adequate wealth.
- On the opposite end of the political spectrum, the Marxist view holds that since value is created solely by labour, profits represent an unfair extraction of value.
- Thus, all forms of billionaire consumption is illegitimate, since private riches are generated through a denial of the rightful claims of workers.
- The co-existence of a large working class with low wages and a small number of billionaires does not arise because of a faulty market mechanism, but is an undeniable feature of capitalism itself.
- The rights over private property enshrined in liberal societies hide deep structural imbalances that serve to continually enrich a few at the expense of the many; in this framework, there can be no way to justify billionaire consumption.
The impact on the economy
- Another defence of billionaire consumption is that regardless of the ethical issues involved, as long as consumption is done domestically, the expansion of purchasing power leads to an increase in demand for locally-made goods, and an increase in domestic employment and incomes.
- In economies like India where the generation of suitable employment is a matter of grave concern, private consumption of the rich ensures a vital boost to aggregate demand.
- Yet this represents a second-best solution to the problem of demand, since what is required for growth in living standards is investment, not consumption.
- Consider two sectors in an economy, a consumption sector that produces clothes, and an investment sector that produces sewing machines.
- Consumption spending does not necessarily generate investment spending, but investment spending, through the working of the multiplier effect, necessarily increases demand in the consumption sector as well.
- Moreover, investment would ensure the capital stock is upgraded with the latest machinery, increasing the productivity of labour and per capita incomes.
- Long-run growth crucially depends on investment spending, which is the domain of the rich, since working classes do not control the operations of businesses and have no say in the prospects of capital expansion.
A “social contract”
- According to the celebrated British economist John Maynard Keynes, capitalist societies rest on a peculiar social contract.
- The capitalist classes are allowed greater wealth, control of production and a substantial share of net output produced each year, provided they ensure high levels of investment that generate sufficient employment and rising productivity.
- They must also ensure that prices are not increased drastically so that real wages do not fall.
- This can be the only grounds for an unequal distribution of resources in a capitalist society from a Keynesian perspective. The greater the share of profits invested, the greater is economic welfare.
- Keynesian growth theory specifies that the rate of growth is highest when the entire share of profits is invested.
- In mainstream growth theory, the level of per capita consumption is highest when the entirety of profits is invested; this is known as the “Golden Rule”.
- Conspicuous consumption out of profits can therefore be seen as reducing the amount available for investment, and hence reducing welfare.
- Herein lies the peculiar problems that affect modern capitalism. Since profits accrue privately, the decision to invest is also taken privately.
- In certain instances, capitalists may wish not to invest, for the risks would certainly outweigh the potential benefits. They may also choose to engage in pure consumption and lavish ceremonies, and liberal societies allow them the uncontested right to do so.
- But this represents a loss for the working classes, since it draws resources away from the expansion of the capital stock, reducing employment and labour productivity growth.
- Modern societies have granted capitalists the right to profit, but cannot extract from them a duty to invest, specifically during times of economic recessions.
- In contrast, workers have no right over the very aspect of spending — investments — that affects their employment and living standards.
- This takes added significance in the presence of monopoly, where even if investment occurs, working classes are affected through the imposition of monopoly prices that reduce real wages and purchasing power.
- The purpose of this piece is not to point fingers at specific instances of conspicuous consumption, but to place some economic issues in context.
- As opposed to a Marxist analysis, a Keynesian understanding would hold that lavish consumption of the rich is a problem only if enough investment is not forthcoming to absorb those searching for jobs and if the consumption of working classes is curtailed through high monopoly prices.
Conclusion
In the context of high youth unemployment, stagnant real wages and a significant loss of jobs in the informal sector, the stark inequalities on display represent a very real public policy problem that we have shown an inability and unwillingness to confront.
