The evolutionary benefits of the Menopause

In the animal kingdom, the menopause (when the ovaries of females stop producing eggs every month, ending reproduction) can only be found in Humans, Killer Whales and Pilot Whales. But why has this rare characteristic of a loss of reproductive ability evolved? It does not seem to make evolutionary sense for an animal to no longer be able to reproduce and spread its own genes throughout its population. Well, in terms of the Grandmother Hypothesis (first suggested by G.C Williams) this process appears to have evolutionary benefits.

The Grandmother hypothesis is the idea that older parents have greater benefits to the propagation of their genes by only having children to a certain age (age 51 in humans), instead of having more children themselves in their later years. This is because grandparents can be of huge benefit to their own grand children due to the fact that they do not have their own children to expend time and energy on.
For example, when an ancient human mother had a child she'd required to expend energy in the form of milk, as well as supply it with shelter, defend it from predators etc. And if this female had another child, she would have to expend energy on the new offspring as well, which would increase the chance of her offspring dying. A grandmother can aid in looking after her daughters (or her sons sexual partners) offspring by helping in finding food, watching out for predators as well as many other tasks increasing their chance of surviving.

This would be of great benefit to the grandparent as by looking after her grandchildren, more are able to be reproduced, leading to the grandparents genes being passed on to a higher number of offspring.

But why is it of greater evolutionary benefit for the grandmother to aid in producing more grandchildren, rather than being able to produce more offspring herself containing a greater number of her own genes.
Well when producing offspring there are a number of risks. The parent as well as the offspring may die during childbirth, and the parent may not be able to be able to gather the resources to look after the offspring efficiently leading to their mortality. But by a grandmother not being able to produce offspring up to a certain age, and being able to put her time and energy in to looking after her grandchildren, it increases the chance of the survival of herself, and her grandchildren who now have an extra adult watching over them.


-Thomas Glen

The diverse and vibrant Rock Pool environment

RockPools are found in the intertidal zones of the ocean shore, and form when the high tide goes out, leaving pools of water at the surface. Rock pools provide great snooping areas for wildlife lovers not satisfied with spending the day snoozing on the beach, however they are also important and intricate environments for a range of wildlife.


Rock Pools, unlike many other ecosystems, are in a constant state of fluctuations due to tidal activity. As the tide comes in and out, it causes changes in the salinity, oxygen content and temperature of Rock Pools, while introducing new organisms, as well as removing, existing organisms that are unable to withstand the force of the waves.

Due to the constantly changing Rockpool ecosystem, the wildlife that survives in them are well adapted to environmental fluctuations and to the constant force of the waves. For example Limpets (left) use their strong muscular feet to firmly attach themselves to their substrate to decrease the chance of them being washed away by strong tidal activity. Other organisms that live in Rock Pools include Coral, Sea weeds, Clams, Crabs, Barnacles, Anemones, Periwinkles, Fish and a range of other creatures that are able to survive in these small compartmentalised environments.



Many members of the rich diversity of Rock Pool life that are able to survive in these small pools of water do so due to plankton (free floating microscopic organisms) that provide a continuous energy source that fuels this aquatic food chain. The sun is also a major energy source as the sunlight is captured by seaweeds and microscopic algae allowing them to reproduce, which then act as a food source for animal life such as periwinkles, limpets and many others.

So if you find yourself at the Seaside peering into a Rock Pool, don't just marvel at the Crabs or Anemones, but admire the intricate and constantly changing ecosystem that these organisms have made their home.

-Thomas Glen

Why are Birds of Paradise so colourful?

Birds of Paradise are widely considered by many to be some of the most beautiful creatures on the Planet. With their iridescent and erratically structured plumage of rich colour, a heart of stone is required not to be moved by the sight of them.
But why would such characteristics be of evolutionary benefit to these creatures? If anything they are a hindrance as they can get in the way during movement through the treetops and could make flight more difficult, while also making them more visible to predators. 

Well the answer all comes down to an evolutionary mechanism called Sexual Selection.


Sexual Selection (first described by the great Charles Darwin) is defined as the competition for mates causing traits that improve breeding success to be passed to the next generation.
So in simpler terms, if an animal evolves a characteristic that makes it more attractive to the opposite sex, it will be more likely to breed than others without it and pass this characteristic to its offspring.
This mechanism explains the colours of Birds of Paradise. In the past before the colours of this avian lineage had evolved, a Bird of Paradise ancestor may have developed slightly brighter plumage, or larger and more noticeable feathers.
This would have made it more attractive as evolutionarily speaking, if the bird was able to produce such colour and/or patterning while being able to survive the downsides of such characteristics (predation, flight disturbances etc) it was fit and healthy with good genes which would allow the offspring of such a bird to inherit these genes as well. This would, due to continuous evolutionary pressure for these traits lead to greater colours and greater patterning.

Sexual selection explains why Birds of Paradise are so colourful, but the beautiful ones we all know and love are all males. The female Birds of Paradise are dramatically less eye catching, most of which are quite brown and none descript. Why is this?
Well the females are the ones choosing the males that are most aesthetically pleasing to them, and therefore have the best genes.

 The reason evolution has created these characteristic differences between the two sexes (sexual dimorphisms), is all due to differences in offspring investment between the two genders. Females are the ones that produce the eggs, and will have to carry and look after the offspring, taking up their own time and energy to enable the offspring to survive and her genes to be passed on.
Therefore picking a mating partner with good genes is a must to make her huge investment worthwhile.
Whereas male Birds of Paradise produce sperm, do not look after their own offspring, and practice Polygamy (mate with a number of partners). Males produce millions of easy to make sperm, so can afford to spread them far and wide with any partners who will accept them, not really needing to care about the genetic fitness of the females. As females are not sexually selected to be aesthetically attractive, they will remain less extravagant to allow greater camouflage to surrounding vegetation, so as not to attract predators towards them, as well as to their offspring.

To sum up, females choose males with good genes that are shown by their ability to survive with such dramatic feathers patterns, so the females (as the egg carriers) do not waste time and energy on offspring carrying her genes that are unlikely to survive.

Males have easily-produced sperm that they try and spread to as many females as possible by attracting them with their colour and mating rituals, these traits becoming more extravagant over evolutionary time as fitness and health are selected for.

-Thomas Glen

Facebook.com/goodnaturepage

Images: Not my own

How beneficial is ivy to wildlife?

Ivy is an evergreen creeper plant that climbs up trees and walls in a search for sunlight. It is capable of surviving a range of climates and can survive in a range of soil types, which is why it can easily be found completely covering many terrains.

Many people tend to kill ivy when they see it as they believe it is detrimental to Trees, and that they lead to the degradation of buildings. However these are myths, and this plant has a huge number of benefits for a range of wildlife.


Ivy provides a shelter from the elements as well as for hibernation for a range of invertebrates such as Spiders, Hover flies, Froghoppers, Moths, Butterflies and many others.
Butterflies will also commonly use Ivy as an attachment point for their Chrysalises so they can develop from Caterpillars in safety from predators. Small mammals such as Mice or Voles will also use Ivy as areas to nest and to shelter in, and many small birds from Wrens, to Tits and Thrushes will build nests among the leaves.


The flowers that grow on ivy are also of great benefit to wildlife. Ivy flowers usually form during the autumn/winter months, which provides a much needed source of nectar to insect life when other flowers have disappeared. This plant will also produce berries that provide food for a range of bird life.

So if you see Ivy in your garden, or covering a tree, don't listen to the rumours that this plant is detrimental, but admire this fantastic refuge for wildlife.



-Thomas Glen

Facebook.com/goodnaturepage

The evolution of Homosexuality

Why did Homosexuality evolve?

Homosexuality is a natural phenomenon found throughout the animal kingdom, and can be seen not only in Humans, but in many animals such as Lions, Zebra, Penguins, Bears and even Lizards. But how did homosexuality evolve if the members involved cannot reproduce, and are therefore incapable of passing on the genetic components for this characteristic? And what evolutionary purpose does the gay characteristic have for the organisms involved?

Well, scientists do not have a definitive answer yet, but there are a few very interesting ideas that have accumulated substantial evidence.

Sexual antagonistic selection Hypothesis:

Say an allele or group of alleles are passed from a parent to their female offspring that gives them greater feminine features such as wider hips and/or larger breasts, making them more attractive to males.
These features would be beneficial to the female as she would attract more mates and have a larger number of offspring than she would have had without these features.
However, although these alleles are of great benefit to the females, it causes an occasional male sibling with the same alleles to be attracted to the same sex rather than the opposite sex.

Although this male will not be able to reproduce, the advantage to the females would be so beneficial that she will have a good number of offspring allowing this allele to be passed through the generations, leading to more gay men down the line.

Kin selection Hypothesis:

This hypothesis conveys the idea that gay humans greatly aid in bringing up the offspring of their straight, reproducing relatives. If gay people have no young themselves to look after, they can aid in the protection and feeding of nieces and nephews improving their chances of survival.

This benefit to their relatives would allow greater spread of the genes that code for the homosexual characteristic causing it to appear in future generations.

These are the two most popular evolutionary hypotheses for homosexuality in Humans.

There are other ideas to why this behavior develops in human’s .i.e. if a female has a particularly high level of testosterone or progesterone during her fetal stage, she may develop gay preferences, and the same goes for some males if they have a particularly low level of these hormones.

Also, many gay people have been known to have children at a younger age and gone on to become gay later on in their lives causing their genetic traits to be passed on through their offspring.

However this is still being studied and an absolute answer has not been formulated yet, although it is more than likely based on environmental as well as genetic factors.

In the rest of the Animal Kingdom, the reasons for homosexuality are quite different.

Bonobo’s are very promiscuous animals and will mate constantly with different members of their group, not just for reproduction but to cement social bonds, and homosexual behavior within these primate groups help with this.

The all female Whip-tailed lizard’s (left) no longer mate with males (who have disappeared from the population) and reproduce exact female clones of themselves.However, because they require the stimulation of mating by males to ovulate, they will act out the copulation ritual with each other to allow egg laying to occur. This evolved as a way for the female species to hold onto the genes that best helps them survive in their environment without the detrimental addition of genes that would be passed to their offspring by males.

Although homosexuality in many non-human animals is greatly understood, humans are apparently more complicated and the scientific community is still working on an answer.
Although it does seem that although gay people cannot reproduce, there is a true evolutionary benefit to their existence.

-Thomas Glen

Image: hands: Phil Hol
For more info visit: http://www.bbc.co.uk/news/magazine-26089486

Photo prop animals: Don't aid a barbaric industry

Photo-Prop animals: Don't aid a barbaric industry


While on their travels to exotic lands such as Thailand, Japan and China, many tourists may come across people holding beautiful wild animals in public areas.
In this age of smart phones and social media, thousands will get the urge to get a photo with this animal and post it to their Facebook or Instagram pages for their friends to see (paying a small charge to the handler of the animal of course), and giving them a keep sake of themselves with a beautiful creature.

However if these tourists were to delve deeper into the story of these exotic animals, they may not be handing money over or getting a picture so quickly.


Photo-prop animals as they are referred to will usually consist of small animals such as Slow Lorises, Gibbons, Lion Cubs, Bear Cubs,  Fennec Foxes, capuchin Monkeys and others that are easy to handle.

 Most of these animals will have been removed from their natural habitats and from their parents (who are commonly killed as the try to stop their cubs from being taken) and get kept in inappropriately small cages on an inappropriate diet. 

They'll get given drugs to make them more docile, many times have their teeth and/or nails removed so they are less dangerous to handle, and then get paraded around busy streets on the off-chance that an unknowing tourist will pay money for a picture with it.

Taking these wild animals through busy streets is another form of torture. This is because due to the loud noises, flashing cameras and constant handling by the animals handler as well as by paying tourists, the animal will be put through a monumental amount of stress which is incredibly cruel.

So please, if you decide to travel to a foreign country and come across photo prop animals, do not pay these people money for a picture, as this funds the barbaric industry.

-Thomas Glen

Facebook.com/goodnaturepage

Fennec Fox image: Bruno D'Amicis 

How are Drones being used to aid in Conservation?

How are Drones being used to aid in Conservation?

Very recently, unmanned air vehicles known as Drones have been widely discussed in the media. Originally used by the military as a means of surveillance, this technology has become very popular and can now be easily purchased by the common person, some for the surprisingly cheap price of £300. 

Although Drones are detested by many who are worried about Privacy violations at the hands of amateurs who have purchased the technology (no one wants a camera carrying Drone hovering by their bathroom window while they’re in the bath), Zoologists and conservationists have discovered ways Drones can be made useful.

Monitoring wildlife populations:

For Zoologists and conservationists who wish to study and monitor wild animal populations effectively, getting near enough to the organisms in question can be an incredibly difficult task, as disturbing them may affect behaviour, the health of the animals, and could also put the scientists involved in danger especially if the animals being studied are predators such as Lions or Alligators.
Therefore, with the use of Drones, animal populations can be watched from a high enough distance to not disturb them, allowing their numbers to be counted and/or the health and behaviour of the animals to be monitored.

Defending against Poachers:

Many wildlife populations such as Elephants, Rhinos and Pangolins are in constant threat by poachers who wish to sell wild animals for their meat, ivory or whatever else is of value to their customers.
Drones can be used to keep an eye on animal populations and possible poachers that may attempt to hunt them. The organisation “WWF” partakes in Drone use (funded by Google) to provide surveillance of endangered species, allowing the organisms to be protected from wildlife traffickers.

Ecological Surveys:

To study and conserve nature reserves and national parks, surveys of huge areas of land are required which is monumental task to take on by foot. However Drones provide a bird’s eye view of huge swathes of land allowing plant cover, water level fluctuations of lakes and rivers, forest clearance from loggers, ice cover and other environmental changes to be monitored more effectively and quickly.

So while Drones are gaining popularity among the technology nerds, and losing popularity among those with personal privacy in mind, they are nothing but good news for the health and well being of the Natural World.

-Thomas Glen

Photographer: unknown

Tag photo