Cambrian Explosion

   Hello everyone! In this new blog post I will tell you about a life-changing event that happened a long time ago. Scientists thought this is like the 'big bang of biological explosion'. Yes, I am indeed talking about Cambrian Explosion (if you couldn't tell already by the title lol).

   First of all, what is Cambrian Explosion? To put it simply, it’s an event where major animals phyla started to appear. Here are some comparison. These are the organisms from Precambrian era, which were mostly consists of bacteria, protozoa, and the most complex one being Cnidaria or jellyfish.

Ocean life before Cambrian explosion

   However, after Cambrian explosion somehow these organisms had evolved to a much more complex one.

A diverse ocean life after Cambrian explosion

   The ocean life had changed, from simple, abstract, multi-cellular organisms to something that resembles the current phylum in the animal kingdom, mainly arthopodes and molluscs. The animals weren’t the best depiction of the current living species of animals, of course, most of these looked very bizarre. However, there is no doubt that Cambrian explosion was the foundation of modern animal kingdom.

You will not found most of these species in the ocean, but they're still similar tho!

   Cambrian period itself, which started after Cambrian explosion, obviously, happened back in 541 MYA-485.4 MYA. It was the first period of Paleozoic era, which means “ancient life”. It also started the Phanerozoic eon, which is the eon for the first phase of animal and plant life.

Timeline of Earth

   Here we have some examples of the animals living in this period. First and the most famous example is Trilobite. This fossil is a Walliseropstrifurcatus. This creature is considered to be the earliest known Arthopods because it matches the general description of that phylum. Physically, you can clearly see that this creature has segmented body and exoskeleton or hard shell that protect its body.

Walliserops trifurcatus' fossil

   We also have Anomalocaris. This is a part of Arthopod due to the segmented body and exoskeleton as well. However, what makes this and Trilobite different is that this thing is massive. Here’s a scale of Anomalocaris to a 1.8 m human. It’s about 1 metre long, have 32 overlapping plates, and also have mouth that could crush prey. It’s no wonder that this creature is the one of the biggest predator of Cambrian period.

Illustration of Anomalocaris 

   Last but not least, we have Conodonts. This organism is one of the first vertebrate that ever existed. This belongs to Pisces phyla, also known as fish. It’s a part of Agnatha superclass. An example of Agnatha that still lives to this day is Lamprey fish. 

   

Left is Conodonts, right is Lamprey fish. Very similar

   Now you might wonder how Cambrian explosion happened. There is still no conclusive conclusion to this, however there are several theories about it. The most popular one is the rise of oxygen in the sea due to phytoplankton booming in the ocean. Changes in the chemistry in the ocean caused by erosion allowed animals to develop things like shells and exoskeletons. However, some studies found that the oxygen rise has no significance at all. Some scientists even argued that Cambrian explosions happened because of the lack of oxygen.

   Regardless of the cause, there’s no doubt that this event changed life on Earth. It’s still the biggest “biological explosion” event that happened in the history, comparable to Big Bang. It’s even more revolutionary than dinosaur era despite that it’s relatively unknown to the masses. Without Cambrian explosion, who knows how life would look like? Would humans event exist without it?

   Thank you so much guys for reading this post, I know it's very rushed but I hope that you will gain some knowledge from this! See you next time!

Axolotl, The Cutest Amphibia Ever

Hello readers! Today I'm, going to show you the best and the cutest amphibia in the world (at least in my own opinion) and that is..... Axolotl. What a cute yet confusing name, right? And now I'm going to explain to you every single bit Axolotl information that I could find.

It looks dumb. I love it

General Description
Axolotl (latin: Ambystoma mexicanum), also known as Mexican Salamander or Mexican Walking Fish, is a neotenic salamander, closely related to Tiger Salamander. Don't let the name "walking fish" fools you, because this is NOT a fish. Axolotl is an amphibia, as I said clearly in the title. This creature was originated in Mexico, obviously. It was found in Lake Xochimilco and Chalco, Mexico City. The name originated from the Aztecs, "atl" means water and "xolotl" means monster. So, literally Axolotl means "water monster". What an edgy name for such a cute creature! Here is the scientific classification for Axolotl.

SCIENTIFIC CLASSIFICATION

Axolotl

Kingdom: Animalia

Phylum: Cordata

Class: Amphibia

Order: Urodela

Family: Ambystomadiae

Genus: Ambystoma

Species: Ambystoma mexicanum

Physical Description
The length of Axolotl can reach about 30 centimeters (12 inches), although the average length is 23 cm. The mass range is about 60 to 110 g. Axolotl's most notable physical feature is its gills, which protrude from the back of its wide head and remain there throughout adulthood. Its legs are short. It has four fingers on each of its front legs and five toes on each of its back legs. In the wild, its coloration is dark, but an albino variety has been bred in captivity. 

Original Axolotl (the dark one) and its albino cousin (the white one)

Habitat
Axolotl is found in freshwater, especially lakes and ponds. However, it's only found in Mexico, specifically Lake Xochimilco. "But what about Lake Chilco?" you asked yourself. Yes, it was found in this lake as well, however, Lake Chalco no longer exists as it was artificially drained to avoid periodic flooding. The water temperature in Xochimilco rarely rises above 20 °C (68 °F), though it may fall to 6 to 7 °C in the winter, and perhaps lower. The average elevation of its habitat is 2290 m.

Diet
Axolotls are carnivores, implying they require a meat-based diet. They have rather rudimentary teeth, designed for gripping rather than biting or tearing. As a result, their food is generally swallowed whole, so anything they want to eat must fit into their mouths. They mostly eat earthworms, bloodworms, and blackworms. They are all very nutritious. If you keep Axolotl as a pet, you can also give them dried food such as soft salmon diet pellets. 

Reproduction

Axolotl's life cycle is neotenic/paedomorphic, which means that it retains larval characteristics in the reproductively mature adult form. Juvenile and adult axolotls possess feathery, external gills and tail fins suited to an aquatic lifestyle. Metamorphosis can be induced in axolotls via thyroid hormone injections. In the wild, axolotls rarely, if ever, metamorphose.

Axolotl eggs

Here's how axolotls mate. It first involves each animal nudging the other's cloacal region, eventually leading to a "waltz," with both animals moving in a circle. Next, the male moves away while undulating the posterior part of his body and tail (resembling a "hula dance"), and the female follows. The male will deposit a spermatophore (a cone-shaped jelly mass with a sperm cap) by vigorously shaking his tail for about half a minute, and will then move forward one body length. The female then moves over the spermatophore, also shaking her tail, and picks up the spermatophore with her cloaca. Eggs are surrounded by a protective jelly coat and are laid singly, unlike frog eggs (which are laid in clumped masses), because they possess higher oxygen requirements. They are often attached to substrates such as rocks or floating vegetation.

The picture above is a life cycle of an Axolotl. An axolotl has five stages in its life, not including death. Stage 1 is the embryo, which measures about 2 mm in diameter, and also the surrounding layers of jelly. Stage 2 is the embryo right before it hatches. In the second stage, the embryo is 11 mm in diameter. Stage 3 is the young larva before it has grown any limbs.  An axolotls skin tends to be very thin and see-through when it is a larva for their first few weeks of life, or until the skin has thickened, so the organs are quite visible. After about two weeks, the larva reaches stage 4. Like other salamanders and unlike other frogs, the front legs come in first and the back legs develop second. At stage 5 the axolotl is a miniature adult.  Axolotl stay in stage 5 for the rest of their lives until they die. 

Smol

Axolotls breed once every year or anually. They mostly breed on March to June. The eggs hatch around 10 to 14 days. The average axolotls can start breeding when they are 1 years old.

Lifespan and Behaviour
Averagely, Axolotl can live 5 to 6 years old on wild, however they can live up to 6 years if they're on captive. Axolotls are nocturnal, which means they are active on the night. They communicate mainly by chemical cues and visual cues. They mostly communicate when mating. Other than that, they rarely communicate to each other. To detect prey and learn about their environment, axolotls can detect electrical fields and use chemical cues.

Uniqueness

A diagram about axolotl's regeneration

Axolotls are often called "master of regeneration". I mean, most salamanders can, however, Axolotls are one of a kind. It can regenerate multiple structures like limbs, jaws, tail, spinal cord, skin and more without evidence of scarring throughout their lives. Axolotls can even receive transplanted organs from other individuals and accept them without rejection. You can cut the spinal cord, crush it, remove a segment, and it will regenerate. You can cut the limbs at any level - the wrist, the elbow, the upper arm - and it will regenerate, and it's perfect. There is nothing missing, there's no scarring on the skin at the site of amputation, every tissue is replaced. They can regenerate the same limb 50, 60, 100 times. And every time: perfect. Amazing, isn't it? As if that isn't incredible enough, the axolotl is also over 1,000 times more resistant to cancer than mammals. According to Professor Stephan Roy along with his team, here's how it works. One of the first steps that occur in the regenerative pathway after amputation is the process known as the de-differentiation of cells. These cells then create a structure known as a blastema, which is a rounded cover on the wound where the newly de-differentiated cells congregate. This structure then develops into a fully functional limb, with no sign of the previous damage. What a great creature! Professor Roy also stated that he and his team hoped that this regeneration mechanism can apply to a human. Possible, but maybe not now since the technology is limited.

Conversation Status

As I mentioned before, one of the natural habitat of Axolotls is gone, which is Lake Chilco. It was drained artificially. Lake Xochimilco isn't much better either since currently it's just swamp and scattering canals. Due to this condition, Axolotls are classified as critically endangered. The number of Axolotl’s has been dramatically decreased over the past 20 years, there is only approximately an average of 700-1200 axolotl’s left in the wild! The main cause for this is the Axolotls decreasing habitat and introduced predators such as carp and tilapia dominating the little area they have left. Ever since these predators have been introduced to the lakes of Mexico the axolotls immediately began to struggle as it was being too heavily hunted upon. We can save axolotls by making canals so that they are save from predators or kept them as pet, which is perfectly legal.

Axolotls are considered critically endangered by scientists. The number of Axolotl’s has been dramatically decreased over the past 20 years, there is only approximately an average of 700-1200 axolotl’s left in the wild! The main cause for this is the Axolotls decreasing habitat and introduced predators such as carp and tilapia dominating the little area they have left. Ever since these predators have been introduced to the lakes of Mexico the axolotls immediately began to struggle as it was being too heavily hunted upon. Also, just a reminder that Lake Chilco is gone because it was drained artificially, and Lake Xicomilcho is nothing but swamps and scattering canals nowadays. You can save axolotls by building canals for them so that they are safe from predators or keep them as a pet because it's perfectly legal and they make a good pet!

AAAAAAAAAAAAAAAAAAAAAA

And that concludes the story of axolotls. A very cute and unique amphibia. I hope you can gain one or two information about axolotls after reading this post! See you later!
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QUESTIONS
1. What is the latin name of Axolotl?
Ambystoma mexicana.
2. Where can we found axolotl in the wild?
In Lake Chilco and Lake Xochimilco, Mexico City.
3. What does the term "axolotl" literally means?
Water monster.
4. How many breed of axolotl exist in the world?
2 breeds, which are the black one and the albino one.
5. Why is axolotl considered critically endangered?
Because their habitats are missing so predators such as tilapia and carp are able to hunt them easily.

--

Source:

http://animaldiversity.org/accounts/Ambystoma_mexicanum/

https://en.wikipedia.org/wiki/Axolotl

https://sites.google.com/site/axolotljc2013/axolotl-life-cycle

http://www.axolotl.org/feeding.htm
https://blogs.scientificamerican.com/guest-blog/regeneration-the-axolotl-story/

Cockroaches

   I have a severe katsaridaphobia. Sounds fancy, right? Well, it's actually a phobia that I'm sure most people have. It's a fear of cockroaches. It's really hard to explain why I feared cockroaches so much. Their body shapes are just so bizarre and disgusting, not to mention the trail of bacteria they left whenever they walk. I hate them so much and I really want to kill all cockroaches in this planet. But apparently, cockroach is one of the most powerful insects in the world. They can survive nuclear apocalypse! So it's pretty much impossible to do some kind of cockroach genocide or something. Anyway, I have this traumatic experience that I will never forget. It's related with cockroaches, so prepare to be disgusted.

   It was 1 AM. I was asleep and still dreaming. But my dream was faded into black when I felt some kind of creature crawling on my body. I was half conscious at that time, so I thought it was just some kind of "hallucination". I swept those "crawling feelings" away. Strangely, it always came back. When that feeling came back in the third time, I opened my eyes and I was extremely shocked by what I saw.

Cockroach.

It crawled on my body.

   I immediately jumped from my bed and shivers in fear. It seems like I just saw some spooky ghost, even though in reality it's just a bug. I searched for Baygon in my room, but I can't find it anywhere. I panicked, the only weapon that I can use to attack those horrible creatures wasn't available on my eyesight. Meanwhile, the cockroach kept crawling on my bed. My breath was shortened. It felt like I was having a severe panic attack. And what makes it worse is that the cockroach was getting closer to me. I screamed in fear, it was an immediate reflex.

Then I saw the thing that I needed the most above my cupboard.

Baygon.

   I hurrily grab that bug-killing bottle and spray it on the cockroach. The cockroach responded by running so fast to every corner. I sprayed it again and again, almost to the point where I could be poisoned. But what did the cockroach do?

It flew.

   Flying cockroach was one of the most spookiest thing I have every witness. I was so desperate, I need someone's help to kill that bug, so I immediately opened my door and ran away and kept screaming loudly. Apparently, my brother was awake and asked why I screamed. I told him the story of the cockroach. I begged him to help me kill that cockroach. He sighed, went to my room and noticed how toxic the smell was. He asked why I used Baygon so much, and I only responded with shivers. When he saw the cockroach, he grabbed a broom and smashed the cockroach a few times until it died. "You could've done that, you know. The broom was on your room." he said. I thanked him a bunch of times until my brother was tired of hearing it.  He went to his room and I went to mine as well. I tried to calm down but I was still afraid that there would be another cockroach passing by, so I stayed awake until 3 AM. Apparently, there's none, so I fell asleep and thankfully, my dream didn't contain any cockroach.