What is the purpose of the male sex?

This is a biological question and not a ‘sexist’ question.

It is biologically quite possible to clone animals, and even in nature some animals can reproduce without needing the male sex. Plants can be reproduced vegetatively, or by using runners etc. So why on earth does nature go to so much trouble to have two sexes ?!

This question I have asked many of my adult science students, and a great many of them realised that they did not really understand why there is a male sex – from a biological point of view?

The history and necessity of ‘sex’

Hundreds of millions of years ago dinosaurs had male and female sexes and so did animals and plants though-out many millions of years before that. So why has sex proved to be so successful and necessary from an evolutionary point of view?

Consider what is happening right now with the outbreak of the tragic and deadly Ebola virus disease? Over half of the people infected with Ebola die, and if it were not for medical intervention it is estimated that maybe 90% of infected people would die. The survivors had been able to combat the disease due primarily to their genetic capabilities – some were able to produce effective antibodies. The survivors may then pass this capability onto their children.  So this might still be possible without males, but for genetic reasons such inheritance is passed on much more effectively with two sexes.

Male and female sex enables a healthy genetic diversity to be maintained, and a regular recombination of the animal or plant genes to give a far better chance of surviving diseases and other environmental threats, as well as adapting to opportunities. In contrast, if a population is all genetically identical (clones) and a disease outbreak occurs it is very likely going to kill off the entire population – this is one of the threats for example to some banana and other crops which are agricultural clones.

Crops varieties which have been selected for their ‘self-fertilisation’ sexual tendencies can also be genetically weakened since this is a form of ‘in-breeding’, although this does enable production of seed and fruit. For optimum healthy crop yields a significant ‘cross-fertilisation’ between different plants is ideally required. Millions of years of evolution have refined bees as efficient mechanisms to enable both self and cross-fertilisation so that both the plants and the bees benefit from the relationship.

The greatest yields in crops such as mangos, coffee etc may be obtained from a combination of selective plant breeding and agricultural methods that include a clear understanding of the need for plant ‘sex’.  The pollination environment critically should include the native honeybee species which are well-adapted to the tropical Philippine environment and are proven excellent enablers of plant ‘sex’.

New diseases and other threats, as well as the need to adapt and succeed at obtaining food etc are issues that occur frequently in nature and so biologically it has proved over time that both the male and female sexes are absolutely necessary. The process of sex is incredibly important to ensure healthy and adaptable offspring. Sex in plants and animals is an ‘evolutionary reality’. We experience sex as humans and see it happen in animals, but not so obviously in plants.

Sex deprivation amongst the crop plants in the Philippines

Unless we are observant we do not see sex happen in plants, and a great many people just do not realise that plants have sex (pollination).  Sex is a biological necessity for plants to produce seeds and fruit

Unless it is adequately taught in schools, the media or in the community, it is unlikely that this knowledge could benefit the great majority of people who live in rural areas and owe their living in some form to agriculture. In the Philippines such a situation is contributing to a pollination crisis causing particular crops to be deprived of sufficient opportunities for sex to produce good yields.

We do not see the billions and billions of microscopic male pollen particles blown around on the wind to pollinate the rice and cereal crops, but they are there and these crop yields in the Philippines are not limited by insufficient sex.

The majority of plant species however produce flowers to attract bees and other insects so that they can have sex – bees transport male pollen particles efficiently between flowers.  There is a long tradition of indiscriminate honey hunting in the Philippines – destructive honey hunting and other activities are degrading the honeybee population.  Such relentless removal of the bees from the environment is causing flowering plants to be deprived of sufficient sex – fewer male pollen particles reach female stigmas and so fewer healthy seeds and fruits are produced.

Resolving the pollination ‘sex’ crisis in Philippine agriculture

Research indicates that the great majority of honey hunters and other rural people are unaware of the wider consequences of the honey hunting methods used – other than bee colonies getting harder to find. Government and universities have not attempted to improve the situation, apparently because it has not been considered an ‘issue’.

The Philippine situation with many agricultural crops could be likened to a ‘slow motion car crash’. Insufficient diligence by the drivers has allowed a situation to occur where the essential honeybee pollinators are degraded by honey hunting and other activities, causing a progressive breakdown of the mechanism that produces the crops and incomes.  As the crash is happening, the drivers try various avoidance tactics but the brakes just don’t seem to work and it seems like the inevitable ‘crunch’ cannot be averted.

What is offered in this website is a well-evidenced assessment of a key underlying cause of the dwindling crop yields in the Philippine and a set of strategic proposals to improve the situation. Philippine agricultural and educational government officials, professors and teachers should be engaging with and leading this debate. If you disagree with the reasoning and proposals offered here you have a duty to offer other viewpoints and information. If you agree then please ensure that other people are also informed of the situation, and participate in working towards a solution to this serious problem which profoundly impacts on the Philippine environment, and damages the livelihoods and prospects of millions of people.

You are welcome to offer your opinion in the ‘leave a comment’ form below.

About Julian

Julian Wright is a British agricultural scientist married to a Philippine teacher, who has a house and some land planted to coconuts and other crops near Dumaguete in the Philippines.
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