Why Dolphins are mammal; not fish?

Photo: Dolphin (Taken from: Sciencealert)

"Even though they live in the ocean all of the time, dolphins are mammals, not fish. Also, dolphins are different than "dolphinfish," which are also known as mahi-mahi.

Like every mammal, dolphins are warm blooded. Unlike fish, who breathe through gills, dolphins breathe air using lungs. Dolphins must make frequent trips to the surface of the water to catch a breath. The blowhole on top of a dolphin's head acts as a "nose," making it easy for the dolphin to surface for air.

Other characteristics of dolphins that make them mammals rather than fish are that they give birth to live young rather than laying eggs and they feed their young with milk. Also, like all mammals, dolphins even have a tiny amount of hair, right around the blowhole.

Whales and porpoises are also mammals. There are 75 species of dolphins, whales, and porpoises living in the ocean. They are the only mammals, other than manatees, that spend their entire lives in the water.

An area of Florida Keys National Marine Sanctuary is home to a resident group of bottlenose dolphins. Many businesses conduct dolphin tours in this area, which can stress the dolphins. To help reduce disruption to dolphins in the sanctuary, the Office of National Marine Sanctuaries, National Marine Fisheries Service, the Dolphin Ecology Project, and the Whale and Dolphin Conservation Society created the Dolphin SMART program. This program recognizes businesses that promote responsible viewing of wild dolphins."

Acknowledgment: Florida-keys

Common Features Between Human and Birds

Photo: Birds having human feelings (Taken from: Pinterest)

Most everyone is aware of at least some of the differences between birds and mammals. Whereas birds have feathers, lack teeth and lay eggs, mammals have fur or hair for insulation, possess teeth and give birth to live young. Although birds are more closely related to reptiles than mammals, birds and mammals have several characteristics in common.

WARM-BLOODED

Both birds and mammals are warm-blooded, which means they can maintain a constant body temperature and do not need to rely on an external heat source to stay warm. This similarity lends itself to several other commonalities, such as similar caloric requirements by weight and the ability to remain active in colder temperatures. Cold-blooded animals, such as reptiles, do not have to eat as much, but they also cannot survive colder temperatures. Being warm-blooded also gives birds and mammals the unique ability to live on any landmass on Earth.

VERTEBRATES

All mammal and bird species are classified as vertebrates, meaning they have backbones and skeletal systems made of bone. Birds, however, have hollow bones with a crisscrossed matrix for added strength. The hollow bones are lightweight, which allows the bird to take flight, while the structural matrix adds strength to withstand the pressure of taking off and landing. 

HEART

Birds require a lot of energy in order to fly. This also necessitates a circulatory system that is both efficient and effective, so they have evolved a four-chambered heart with two atria and two ventricles, just like mammals. One of the main benefits of this type of circulatory system is that it allows the separation of oxygenated and deoxygenated blood. Other species of animals, such as reptiles, have hearts with fewer chambers, which means a much less efficient model.

BLOOD

The blood of birds and mammals contains both red and white blood cells, called erythrocytes and leukocytes respectively. The red blood cells in both classes of animals contain hemoglobin, a protein containing iron that is responsible for oxygen transport and gives blood its red color.

CARING FOR YOUNG

Another similarity between birds and mammals is that both classes care for their young after they're hatched or born. The length of time varies from species to species, depending on the age that the young are first able to take care of themselves. Female mammals feed their young by lactating, while birds feed their young beak to beak.

VOICE

In fact, birds – at least some of the species we have studied – have a surprising number of things in common with humans when it comes to using voice as communication. Both birds and humans can learn how to use their voice, and some birds and humans can even mimic other species – the best proof that vocalisation is a learned behaviour. Australian magpies and lyrebirds are probably the most outstanding mimics in the world. Both species have pure tone, beautiful sounding song and extensive repertoires.

There are reports of people who, hearing the neighing of a horse where no horse should be, were driven by curiosity to check in the yard. Moving to the source of the sound, they saw a magpie sitting in a tree doing a mighty good imitation of a horse. Incidentally, a true-blue Aussie budgerigar is the Guinness World Records holder among birds in the number of words it can mimic – more than 1,700 English words!

FEELINGS

We now know that birds can have multiple and remarkable cognitive abilities. They can also feel, have empathy and even grieve for the death of a partner; magpies in particular, apart from parrots, can form long-term friendships with humans or their dogs.

So the next time you look at a bird, remember they are not as different from us as you might think!

Acknowledgment: Imperial college London, Quora.com, The Guardian, Wingspan

Weekly Reading Practice-01: For GRE/IELTS/TOEFL/BCS/BANK

I.M.B: SAU BLOG OF AGRICULTURE

Passage-01, Line-1 to 10:

A simple list of Isaiah Berlin’s principal beliefs, stripped of the rich detail and nuance that he always supplied, may strike the reader as so obvious as to be banal; yet his positions have not always been taken as obvious. Berlin occasionally defined genius as the ability to turn a paradox into a platitude, and part of his own genius was to effect such a transformation about matters central to human self-understanding, which he saw as the fundamental objective of philosophy. “Know thyself”, as the ancient maxim has it. Consider the summary of Berlin’s views that follows: how many of them were once, or still are, considered controversial?

Passage-02, Line-11 to 18:

Definitive, universal answers to most moral and political questions are in principle impossible, so that the attempt to impose such answers, especially by force, is never justified. There is often more than one right answer, partly because human values and the cultures they variously contribute to are irreducibly distinct from one another – cannot be translated into the terms of a common denominator. Nor, therefore, can either values or cultures be ranked in an objective hierarchy.

Passage-03, Line-19 to 28:

Not all needs, desires and values are shared by everyone, but many are common to the great majority of human beings, whatever time, place or society they belong to. If it were not so, we could not understand, assess and communicate with others. One of our shared needs is to belong to a community whose language and form of life we can effortlessly negotiate, recognizing them as a central part of our identity. This is the basis of cultural nationalism, a peaceable cousin of political nationalism, and one we should not aspire to eliminate in favour of cosmopolitanism, which Berlin called “the shedding of all that makes one most human”.

Source: aldaily

A brief introduction to plants that keep mosquitoes away

Photo: Lavender

It’s hard to enjoy warm weather when mosquitoes are around. Mosquito bites can be itchy, painful, and annoying. Instead of buying creams and sprays with harmful ingredients, turn toward nature. These nine plants can naturally protect you from mosquitoes.

Citronella

Citronella grass will cover up scents that attract mosquitoes. But since it can grow up to 5 or 6 feet tall, make sure you have space! Growing this plant is a safer alternative than lighting citronella candles.

Rosemary

Humans might like the smell of rosemary, but mosquitoes hate it. Keep some on your windowsill or herb garden. You can even add a few stem to your table centrepiece.

Marigold

Marigolds give off a scent that mosquitoes don’t like. In fact, farmers even use marigolds to make a border around their crops. They’re also one of the easiest plants to grow.

Basil

All kinds of basil can ward off mosquitoes. It can even keep away flies. This herb loves the sun but can be grown both indoors and outdoors.

Lavender

Known for its lovely scent, lavender is another natural repellent. It’s also pretty to look at! Lavender also loves the sun and doesn’t need to be watered often. They’re great if you don’t have a green thumb.

Catnip

Catnip is a type of mint that will drive mosquitoes away. But if you have a cat, keep in mind that it will try to play with the catnip. This herb can also attract stray cats, so be careful where you place it.

Chrysanthemum

Also known as “mums”, these colourful flowers are easy to care for. They can also be used as border plants like marigolds. Aside from mosquitoes, mums can also keep fleas and ticks away.

Venus Flytrap

If mosquitoes and other bugs sneak into your home, a Venus flytrap can save the day. This carnivorous plant thrives best in tropical climates and loves the sun. It will naturally feed itself, so don’t try to force it.

Peppermint

The powerful smell of peppermint can also help. It works well in a windowsill herb garden next to rosemary, catnip, and basil. Water it lightly every day.

Make mosquito repellent by yourself

You can also make a mosquito repellent with the herbs on this list. Just crush up the leaves and mix with coconut oil or another natural lotion. Citronella can also be used for this purpose.

Acknowledgment: The Independent, Wallpaper Abyss

Introduction to MUNNAMATH.COM: A helping hand to your career development

Photo: Logo of munnamath.com

Introduction to Munnamath.com: 

Munnamath.com is a partially non-profit website featuring with necessary materials that will help a student building his/her career. The major characteristics of the site is that it tries to amalgamate basic study materials at a common place needed daily for a student.

Services Provided by the Website:

The website currently aimed at providing three types of services

1). Non-paid services: Completely free study materials

2). paid Services: The site presents some paid study materials. It is because, producing these materials demanded enough time and physical-mental hard works. 

3). Freelance services: Contractual freelance services like data entry, data analysis, data interpretation, making graphs and tables on the basis of analysis are also provided by the website.

Link to the website:

To visit the the website, please, click on the following link

MUNNAMATH

Search the website on search engines:

You may find the site by typing the keyword "munnamath" on your browser. The preview of search is shown in the figure below: 

Photo: munnamath.com on search engine suggestion 

Green: The color of nature

Photo: Featuring green lush

Reviewed By: M A Mannan Munna

Green, the color of life, renewal, nature, and energy, is associated with meanings of growth, harmony, freshness, safety, fertility, and environment. Green is also traditionally associated with money, finances, banking, ambition, greed, jealousy, and wall street.

The color green has healing power and is understood to be the most restful and relaxing color for the human eye to view. Green can help enhance vision, stability and endurance. Green takes up more space in the spectrum visible to the human eye and it is the dominant color in the natural. It is a natural choice in interior design as an ideal background or backdrop because we as humans are so used to seeing it everywhere.

The color green affects us physically and mentally in several different ways. Green is soothing, relaxing, and youthful. Green is a color that helps alleviate anxiety, depression, and nervousness. Green also brings with it a sense of hope, health, adventure, and renewal, as well as self-control, compassion, and harmony.The green color is often used to indicate safety in the advertising of drugs and medical products. Green is directly related to nature and energy, so it is also commonly used to represent and promote ‘green’ products.

Green Is Exciting

While some find green a relaxing color, others find that it gives them a feeling of excitement. "Green gives me a rush. I buy everything in green, and like pictures with a lot of green in them. I like characters with green hair, eyes, clothes automatically. It gives me an endorphin rush, I think," said one viewer.

This can be especially true of particularly vibrant shades of green. "I love a really bright, vibrant green! It seems so energetic and motivating. Like I always feel inspired and recharged whenever I'm around a bright chartreuse or lime green," explained a reader.

"When I see someone is wearing the color green, I feel she is kind, helpful, caring and sympathetic. It is a color that just radiates compassion." - Yeganeh

"Green to me is a symbol of growth of nature. When I notice the color green it gives off a calming and peaceful feeling." - Brenden

"The color green reminds me of the natural world. I love to incorporate green in my interior decor and wardrobe because it feels so close to nature." - Betty

"Hopeful, optimistic, forgiven, energized, restful, royal, elegant, rich, healthy, playful, respected, responsible, wealthy, cautious, peaceful, warm, stable, tall, clean, stable, comforted, sturdy, strong, and compassionate. This is my favorite color, all shades and hues." - Joe

"Green is a color that to me symbolizes a new beginning. I imagine a fresh green plant emerging from the soil. Whenever I'm trying to get motivated to tackle a new goal or start over on something, surrounding myself with green can be quite helpful." - Ivan

Acknowledgment: BOURNCREATIVE, VERYWELLMIND.COM, TIMES OF INDIA, ALJANH

PUBLIC URINATION: FACTS AND FALLACIES

A man urinating publicly (P.C,: Md. Ashiqur Rahman)

Editor: M A Mannan Munna

Facts of Public Urination in Dhaka City

Roadside urination is a very common incident that impacts on both environment and public health. A randomized face to face field survey was conducted at different spots. Rickshaw puller is the main group who urinate at roadside. People are necessitated to urinate at roadside due to insufficiency of public sanitation facilities. Roadside urination is one of the crucial barriers for improving the sanitation situation of the city. Mass migration, uncontrolled population growths, unplanned urbanization and lack of proper sanitation facilities (i.e. public/mobile toilets) are accelerating roadside urination in Dhaka city which impacts on society, environment and public health. As such this research focused very first time on this unhygienic but frequent incident of the city. Randomized face to face field survey was conducted at different roadside urination spots and public toilet locations in Dhaka South City Corporation (DSCC). Four different questionnaire forms were prepared to cover four different groups of people. The survey covered total 364 people. Among ten different professions of urinators rickshaw puller was the main group who urinate at roadside. Majority percentages (80%) of people were found aware of this unacceptable practice but they were bound to urinate at roadside due to intense insufficiency of public sanitation facilities. Lack of law enforcement was also accountable for remaining this problem. Nearly half of the users were unsatisfied about the hygienic conditions of the existing public toilets. More than 70% of people relied on the effectiveness of privatization of this sector. The findings revealed that the frequent incident of roadside urination is one of the major barriers for improving overall sanitation practice of the city.

Health and Environmental Hazards

If someone have urinary tract infection, the bacteria in his urine can spread, infecting other people and causing disease. On urination on soil, the bacteria get a fertile breeding place and multiply. Worse, children playing may touch the soil with their hands or play barefoot, infecting them. The urea content in urine attracts flies and cockroaches. These insects are carriers of bacteria, including the ones found in urine, and can pass them on in exposed food and water.

What can be done

Raising voices not eyebrows is the only solution to this offensive crime, only then a slow but certain change will come one day for sure. It is true that Nature’s call is not something to be avoided but women have been brought up, trained to use a urinal only when one is available. It is time that men also will start to train themselves and keep the environment clean and healthy.

Acknowledgment: Research Gate, Loupdargent, The better India

Are plant pathogens (Virus, Bacteria and Fungus) fatal to human?: A brief review

Image: Tobacco Mosaic Virus (TMV) under microscope (Science photo library)

Editor: M A Mannan

Effect of plant pathogens on human

Although infection of plants by pathogens can have serious consequences on plant health, human health can be affected by one of the several ways. Viruses, bacteria and fungi that infect plants do not usually cause infection in humans. However, a study reported that Pepper mild mottle virus may react with the immune system of humans and induce a clinical symptom, but the study did not provide a clear evidence on the pathogenic role of this plant virus in humans. Despite the question about the possible direct effect of plant pathogens on humans, several plant pathogens can affect humans by reducing the available food or by contaminating human food with toxic compounds. Human health can also be affected by bacterial species living in agricultural soils and used as bio-control agents for plant diseases.

One of the most common ways by which plant diseases can affect humans is through the secretion of toxic metabolites ’mycotoxins’ by fungi infecting plant products. Although the fungi producing these mycotoxins infect plants but not humans, these mycotoxins can have direct effects on humans and animals, resulting in diseases and death. Examples of fungal species producing mycotoxins include Aspergillus flavus, Fusarium spp. and Penicillium spp. There are several groups of mycotoxins under which several types are included. Aflatoxins are one of the most common and serious groups (types = B1, B2, G1 and G2), which are produced by some Aspergillus species. Aflatoxin B1 is one of the most serious mycotoxins, because it is lethal at high doses and is carcinogenic to humans at low doses and can result in reduced liver function, vomiting and abdominal pain. Annual deaths in some parts of Africa due to the effect of aflatoxin have been reported to reach 250,000 annually. Mycotoxins can be found in several products, especially peanuts, pistachios and maize. Infection of these products by mycotoxin-producing fungi can occur in the field or during storage. In addition, mycotoxins can be consumed indirectly by humans through the consumption of meat from animals fed on food contaminated with mycotoxins.

Humans Have Antibodies against a Plant Virus

Tobacco mosaic virus (TMV), a widespread plant pathogen, is found in tobacco (including cigarettes and smokeless tobacco) as well as in many other plants. Plant viruses do not replicate or cause infection in humans or other mammals. This study was done to determine whether exposure to tobacco products induces an immune response to TMV in humans. Using a sandwich ELISA assay, we detected serum anti-TMV antibodies (IgG, IgG1, IgG3, IgG4, IgA, and IgM) in all subjects enrolled in the study (20 healthy smokers, 20 smokeless-tobacco users, and 20 non-smokers). Smokers had a higher level of serum anti-TMV IgG antibodies than non-smokers, while the serum level of anti-TMV IgA from smokeless tobacco users was lower than smokers and non-smokers. Using bioinformatics, we also found that the human protein TOMM40L (an outer mitochondrial membrane 40 homolog – like translocase) contains a strong homology of six contiguous amino acids to the TMV coat protein, and TOMM40L peptide exhibited cross-reactivity with anti-TMV antibodies. People who smoke cigarettes or other tobacco products experience a lower risk of developing Parkinson’s disease, but the mechanism by which this occurs is unclear. Our results showing molecular mimicry between TMV and human TOMM40L raise the question as to whether TMV has a potential role in smokers against Parkinson’s disease development. The potential mechanisms of molecular mimicry between plant viruses and human disease should be further explored.

Acknowledgment: IJNPND, PLOSONE

Do You know how colorful Grasshopper is!

photo: A splendid Grasshopper

Editor: Nadia Noor Shaki

Grasshoppers are herbivorous insects of the suborder Caelifera in the order Orthoptera. To distinguish them from bush crickets or katydids, they are sometimes referred to as short-horned grasshoppers. Species that change color and behavior at high population densities are called locusts.

A Grasshopper is an amazing insect that can leap 20 times the length of its own body. If you or I could do that, we would be able to jump almost 40 yards!

A Grasshopper does not actually ‘jump’. What they do is use their legs as a catapult. Grasshoppers can both jump and fly and they can reach a speed of 8 miles per hour when flying. There are about 18,000 different species of grasshoppers.

Grasshoppers Characteristics

Grasshoppers are medium to large insects. Adult length is 1 to 7 centimetres, depending on the species. Like their relatives the ‘katydids’ and ‘crickets’, they have chewing mouth parts, two pairs of wings, one narrow and tough, the other wide and flexible, and long hind legs for jumping. They are different from these groups in having short antennae that do not reach very far back on their bodies.

Grasshoppers usually have large eyes, and are colored to blend into their environment, usually a combination of brown, grey or green. In some species the males have bright colors on their wings that they use to attract females. A few species eat toxic plants, and keep the toxins in their bodies for protection. They are brightly colored to warn predators that they taste bad.

Female grasshoppers are larger than the males and have sharp points at the end of their abdomen that are there to help them lay eggs underground. Male grasshoppers sometimes have special structures on their wings that they rub their hind legs on or rub together to make sounds.

Grasshoppers can be found almost everywhere in the world, except for the colder regions near the North and South poles.

Types of Grasshoppers

There are two main groups of grasshoppers:

(1) long-horned grasshoppers

(2) short-horned grasshoppers

Grasshoppers are divided according to the length of their antennae (feelers), which are also called horns. Short-horned grasshoppers are usually called ‘locusts’.

Grasshopper Habitat and Diet

Grasshoppers live in fields, meadows and just about anywhere they can find generous amounts of food to eat. A grasshopper has a hard shell and a full grown grasshopper is about one and a half inches, being so small you would not think they would eat much – but you would be so wrong – they eat lots and lots – an average grasshopper can eat 16 time its own weight.

The grasshoppers favorite foods are grasses, leaves and cereal crops. One particular grasshopper – the Shorthorn grasshopper only eats plants, but it can go berserk and eat every plant in sight – makes you wander where they put it all.

Grasshopper Behavior 

Grasshoppers are most active during the day, but also feed at night. They do not have nests or territories and some species go on long migrations to find new supplies of food. Most species are solitary and only come together to mate, but the migratory species sometimes gather in huge groups of millions or even billions of individuals.

When a grasshopper is picked up, they ‘spit’ a brown liquid which is known as ‘tobacco juice’. Some scientists believe that this liquid may protect grasshoppers from attacks by insects such as ants and other predators – they ‘spit’ the liquid at them then catapult up and fly off quickly.

Grasshoppers also try to escape from their enemies hiding in the grass or among leaves. If you have ever tried to catch grasshoppers in a field, you know how quickly they can disappear by dropping down into the tall grass.

Grasshopper Predators

The grasshoppers greatest enemies include various kinds of flies that lay their eggs in or near grasshopper eggs. After the fly eggs hatch, the newborn flies eat the grasshopper eggs. Some flies will even lay their eggs on the grasshoppers body, even while the grasshopper is flying. The newborn flies then eat the grasshopper. Other enemies of grasshoppers include beetles, birds, mice, snakes and spiders

Acknowledgement : Animal Cloner

Chromatic Biography of Tortoise

Photo : A sea-side tortoise

                                             

Editor: Nadia Noor Shaki

A Tortoise is a land-dwelling reptile of the order Testudines. Tortoises are found worldwide with the most famous tortoise of all, the Giant Tortoise Lonesome George who lives on the Galapagos Islands near Ecuador. Tortoises, like their aquatic cousins, the Turtles, have a hard shell which protects their body.

The top shell is called the carapace (a dorsal section of an exoskeleton or shell) and the bottom is called the plastron (the nearly flat part of the shell structure). The carapace and the plastron are connected by what is called the ‘bridge’. The shell is covered with scutes which are scales that are made of keratin (the same protein that our fingernails are made of). The carapace can help indicate the age of the tortoise by the number of concentric rings, much like the cross-section of a tree.

Many tortoises can retract their head, their four limbs and tail into the shell for protection. Tortoises have a beak but no teeth and no external ears, just two small holes on the sides of the head. Tortoises can vary in size from a few centimetres up to two metres in length. Male tortoises tend to have a longer, protruding neck plate than their female relatives.

Tortoises tend to be diurnal (active during the day) animals with tendencies to be crepuscular (animals that are primarily active during the twilight), depending on the ambient temperatures. Tortoises are generally reclusive and shy creatures.

Tortoise Diet

Most land based tortoises are herbivores, feeding on grazing grasses, weeds, leafy greens, flowers and certain fruits. Their main diet consists of alfalfa, clover, dandelions and leafy weeds.

Tortoise Life Span

Tortoises generally have life spans comparable with those of human beings, however, some tortoises have been known to have lived longer than 150 years.

Tortoise History

Tortoises and Turtles have existed since the era of the dinosaurs, some 300 million years ago. Tortoises and Turtles are the only surviving branch of the even more ancient clade Anapsida, which includes groups such as the procolophonoids, millerettids and pareiasaurs. Most of the anapsids became extinct in the late Permian period, with the exception of the procolophonoids and the precursors of the testudines (turtles and tortoises)

Acknowledgement : Animal Cloner