Hello again!

I hope you are all well! … Good. Now let’s get back to me.

I celebrated my 22nd Birthday the other week! I had a lovely week at home, and I am definitely feeling very spoilt and full of yummy birthday/Easter treats. But nothing could possibly beat my 21st birthday last year. On my actual birthday, my family took me to a Turkish restaurant with belly dancers! The food was delicious and the dancing was a lot of fun! But my parents really upped their game with the presents, and got me a ‘Ranger for the day’ experience at the Wildlife Heritage Foundation (WHF), a big cat sanctuary in Kent. This involved me feeding and cleaning the living areas of the large cats. And much to my surprise when it came to feeding time for the cheetahs, I even got into the enclosure with them!

cheetah
Me stood rather nervously in front of 3 cheetahs!

As part of the experience, I also got to pet a few of the animals, including a puma, snow leopard, a Bengal tiger, and a lion. It was up there with one of the best days of my life! I learnt so much from the experience, and I’d highly recommend it to anyone.

Places like the Wildlife Heritage Foundation are important, because they really focus on the conservation of species, in this case, large cats. They’re actually not open to the public normally, and a lot of the staff there are volunteers. This just shows that they don’t encourage public enjoyment (like zoo’s), but are there purely dedicated to the conservation of these beautiful animals.

Don’t get me wrong though! I love zoos! Zoos can be great, and they often contribute to conservation of species too! In fact, some of the animals at the WHF had been to zoos in the past and were due to in the future, as they had been matched with a member of the opposite sex. Basically, the way effective breeding works in places aimed to increase the population of endangered animals, is through stud books. In these books, all the animals which can contribute to future generations are recorded, where they can be matched with an appropriate individual of the opposite sex. And by appropriate, I mean an individual that is the most genetically different from the individual from the other sex. In fact at the time of visiting the WHF, one of the male lions had just been matched with a female in Africa, so they were preparing to transport the male over there in the next few weeks!

And you thought conservation programmes just involved breeding animals willy nilly! Nope, it’s not that easy I’m afraid. Breeding animals that are most genetically different is important; because it means that offspring are less susceptible to diseases (genetic and non-genetic), and have more capacity to adapt to changing conditions in the future. Therefore future generations are more likely to successfully live on to contribute to the animal population. And so conservation of the species is more likely to be successful, yay!

An example of when low genetic diversity can negatively affect a species, can be seen in white tigers. This trait occurs in offspring when a mother and a father contain a recessive allele for fur colour. Let me explain this a bit for you.

Every characteristic in an individual is made up of 2 alleles at a specific loci in their DNA, where an allele is defined as ‘each of 2 or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome’. These alleles can be either dominant or recessive. So using the example of fur colour in tigers, we will say that the normal colouration in tigers is Yellow and black, so we will call the allele for this ‘Y’, and it is dominant. The allele for white tigers is recessive, so we will give it a lower case ‘y’. So because 2 alleles contribute to a trait, they are always in pairs – one from the mother and one from the father. Dominant alleles are always expressed in an individual, whether it is paired with a dominant allele or a recessive. Recessive alleles are only ever expressed if BOTH the alleles are recessive.

So, if you get a mother and a father that are both dominant for yellow and black stripes, all of the offspring will be yellow and black. However sometimes, the mother and father will both be yellow and black striped, but they may have a recessive allele for colouration, which is disguised as it is not shown in their trait alongside a dominant allele. Therefore they could produce offspring with 2 recessive alleles, which would appear white and black striped. Does that make sense?

Hover over

dominanttwist
2 dominant alleles yellow and black striped tigers produce all yellow and black offspring
recessiveyy
2 fully recessive white and black striped tigers produce all white and black offspring (which would NOT occur in the wild)
Yr
Both parents are yellow and black but have a silent recessive allele, 1/4 of offspring will be black and white (and therefore killed by parents in the wild as this is disadvantageous)
YY
Parents yellow and black but have a silent recessive allele, however this is masked in offspring because both parents have a dominant allele for fur colour

White tigers don’t live to adulthood in the wild. If the mother gives birth to a white tiger, she will kill it. This is because the white colouring is seen as disadvantageous, as it won’t camouflage well and therefore is more likely to be noticed by prey and a disadvantaged predator. Parents in the animal world want their offspring to be as fit as possible, so choosy females often go for characteristics in the opposite sex that are classed as the most fit, and therefore want these genes, along with their own to be carried onto the next generation. Another reason why mothers may kill a white cub would be because she knows that this individual will not be successful during mating when it’s older due to its disadvantaged genes, and so her genes would not be carried on to future generations, which she will not like!

However white tigers are a real beauty to look at. I’m guilty of finding them outstandingly beautiful, that’s why I chose to hand feed the stunning white tiger named Narnia while I was Ranger for the day! Due their beauty and their rarity in the wild, people love to see them and they have become quite the selling point for some zoos. This pressure has led to severe inbreeding of white tigers in captivity, to produce white tigers which people will then pay to see. However this has caused abnormal genetic defects in white tigers, due to the presence of homozygous recessive alleles.

Narnia

*I would just like to add here that Narnia is NOT used in any breeding programme. She is kept at the WHF for her protection.

This example shows why you cannot just cross male with female when it comes to sustainable conservation! To build a population of a species, the breeding pairs must be genetically matched to achieve the most diverse offspring, in order to give the species the most positivity to thrive in the future.

Please do have a look on the Wildlife Heritage Foundation (click for link) website for more information! Like I said earlier, they are not open to the general public, so every help they get – from the ‘Ranger for a day’ experience, to small donations, really makes a difference in keeping great places like this up and running!

Thanks for reading!

Alina

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