Abdul Wahab - science4fun

Nigersaurus are famous dinosaurs for having 500 slender teeth in their jaw. These dinosaurs have been recognized recently in the year 2000 and were named in the honor of country “Niger”. The word Nigersaurus has two parts; Niger (country name), and Saurus (reptile).

Nigersaurus lived around 100 million years ago in a period called the Cretaceous period that lasted from 145 to 66 million years ago. The genus of Nigersaurus contains only one species called ”Nigersaurus Taqueti”.

What Do They Look Like

Nigersaurus is placed in the category of sauropods in which all the long-necked and long-tailed dinosaurs are placed. Nigersaurus was probably one of the smallest sauropods because its neck was short. An adult Nigersaurus weighed around 4 tons and its size was comparable to a modern elephant. The overall length of a typical Nigersaurus was around 9 meters (30 feet) including its tail. It had thick and stronger hind legs as compared to its front legs. Its neck was short and had 13 vertebrae in the cervical spine.

The skull of a Nigersaurus was made of thin bones and had many small openings and pores. These features provided them great flexibility in feeding on the ground. The muzzle of the Nigersaurus was wide and long which helped it in eating small ground-based vegetation. It had around 500 thin teeth in its jaw that were replaced with new teeth in 2 weeks. Its upper jaw teeth were larger than its lower jaw teeth. Moreover, Its jaw was much wider than the skull.

Habitat

Nigersaurus preferred to live in areas having water lakes or streams nearby; the area is also called the riparian zone. Due to plentiful water, a riparian zone has a lot of low-lying vegetation. Riparian zones provide Nigersaurus with many types of vegetation. They thrived on the part of the Earth that we now call as Sahara Desert. However, During the Cretaceous period, the Sahara Desert was very green and hospitable. It was abundant in rivers, lakes, low-lying vegetation, and a variety of plants.

The Sahara Desert in the Cretaceous period was a good region for supporting different dinosaur species. Fossil evidence suggests that Nigersaurus shared their habitats with other dinosaurian herbivores, i.e. Apatosaurus. They also had predators that lived in the same region and one of their predators was theropoda.

Behavior and Lifestyle

Nigersaurus is believed to behave much like other herbivore sauropods. They had probably spent most of their time in hang-dog positions and grazing low-lying vegetation. Nigersaurus had difficulty in holding their head upward or horizontally. So eating leaves and other parts of long trees was not possible for them.

Paleontologists believe that their behavior can be compared with today’s cows. Nigersaurus were social and remained herds as a protection strategy. Due to insufficient fossil evidence, the reproduction strategy of Nigersaurus is not known. However, studying the other related sauropods gives a clue that, they would nest in colonies for laying eggs. They also provided food, care, and protection to their offspring.

Diet

Similar to other Sauropods, Nigersaurus were herbivores. They had grazed close to the ground and ate low-lying vegetation. They had a wide muzzle which helped them in cropping more vegetative material in a single bite. You may think they probably ate grass, but the grass hadn’t evolved during that time. The dental structures of Nigersaurus also suggest that they ate soft plants in large amounts to meet their nutritional requirements. They mostly ate angiosperms, horsetails, and ferns as food. Many paleontologists also believe that their 500 closely packed teeth arrangement also functioned like a comb. This comb-like teeth arrangement may have also helped them in filtering and eating aquatic plants.

Discovery

The first remains of Nigersaurus were discovered in 1976. But paleontologists at that time were not sure about their findings. Paul Sereno, an American paleontologist, led expeditions to Niger in the years 1997 and 2000 for the search of fossils. He discovered many fossils from Elrhaz formations in Niger. Among those fossils, he found fossils of a new dinosaur species that is known as Nigersaurus (“Niger Reptile”). He along with other paleontologists gathered many bony parts of Nigersaurus separately and assembled a rough skeleton.

Paul provided a detailed paper on the appearance of Nigersaurus in 2005. He explained its unusual Skull which housed 500 teeth and its feeding adaptions. However, a more detailed paper on the whole Nigersaurus skeleton came in 2007. Currently, many specimens discovered by other paleontologists are under examination and further details will emerge as the research will continue.

For more information goto: https://en.wikipedia.org/wiki/Nigersaurus

Facts

Nigersaurus means Niger-Lizard, but Nigersaurus are not lizards; they are dinosaurs. Dinosaurs and lizards are a distantly related group of reptiles.
Skull bones of Nigersaurus are very thin, even light could pass through them.
Nigersaurus are also called Mesozoic cows because their behavior was similar to modern cows.
Despite elongated nostrils, Nigersaurus’ sense smell was not so good.
When the first fossils of Nigersaurus were discovered in 1976, paleontologists couldn’t recognize them as a new species. It is because the skeleton fossils were very hollow and distorted.

Trees are one of the most useful and beautiful plants on the Earth. They provide us with fresh oxygen and many necessary things, e.g. wood, fruits, pulp for producing paper, and shade on sunny days. Also, they provide homes to a lot of animals including land animals, insects, and birds.

What is a Tree?

Trees are plants, which look bigger with lots of branches and leaves. There is no proper scientific definition of tress. In general, a plant is considered a tree if its height reaches more than 13 feet, lives for many years, and has a woody stem. Moreover, there are certain features which are common in trees. These features are:

They can grow in the vertical direction.
They have a single main trunk
The trunks of a tree are mostly covered with bark for protection of their inner tissues.
They have many branches emerging from a single trunk. Also, the branches are covered with leaves.

Types of Trees

Trees are very diverse plants that are spread around the world. There are more than 73,000 discovered species of trees. Most of the trees can be categorized into four main types according to their leaves.

Coniferous Trees (Conifers)
Evergreen Trees
Deciduous Trees
Palm Trees

Coniferous Trees (Conifers)

Conifers are mostly known for their scale-like and needle-like leaves which are mostly found in cold climates. Conifers don’t produce flowers for reproduction, but they produce cones for this purpose. These trees belong to a larger group called gymnosperms. Some of the famous conifers are redwoods, cedar trees, and spruce trees.

Evergreen Trees

Evergreen trees, as the name suggests, remain green during all seasons. They don’t shed their leaves completely in the autumn. Evergreen trees have continuous foliage; they grow new leaves that replace the older ones. Also, they release oxygen year-round due to photosynthesis taking place in all seasons. Conifers are also part of evergreen trees because they remain green year-round. Examples of the evergreen trees redwoods, pines, cypresses.

Deciduous Trees

Deciduous trees are known to lose all of their leaves during autumn and remain bare throughout the winter. They grow new leaves each year, unlike the evergreen trees which don’t lose all of their leaves at once. The color of deciduous trees also changes in the autumn. Examples of deciduous trees are beeches, maples, and oaks.

Palm Trees

Palm trees are a very distinct group of trees that are mostly found in tropical and subtropical regions. They have a unique appearance and are mostly characterized by their tall branchless trunks. They have a big crown of large feather-like leaves on their top. There is a large variety of palm trees, but the most famous are coconut palm trees and date palm trees. Palm trees also play an important part in the economy due to palm oil which contributes a significant percentage of worldwide edible oils.

Structure of a Tree

Trees, like any other plant, are structurally interconnected systems to perform vital functions for survival. The main parts of a tree are:

Roots: Roots are part of the trees which remain in the soil. They absorb the water and nutrients from the soil for the whole tree. Also, they provide a strong anchor to hold the trees in strong winds.
Trunk: A trunk provides support and shape to all the parts of a tree. It stores and transports water, nutrients, and food to all of its parts.
Crown: The crown is the topmost part of a tree and is made of branches, sub-branches, leaves, and reproductive parts. The overall appearance of a tree is represented by this structure. It has different shapes and sizes for different trees.
Branches: Branches emerge from the main trunk of a tree for the distribution of leaves in large spaces evenly. They grow at different heights of a tree so that leaves can get the necessary air and sunshine.
Leaves: They are like the food factories for a tree. They produce food in the photosynthesis process and give precious oxygen to animals and humans. Leaves contain a substance called chlorophyll, which gives them a green color and is used in photosynthesis.

Trees and Humans

Trees are giving us food, wood, and many other necessary materials. They provide us with fresh oxygen and help to reduce the pollution. But, we as a human are destroying the trees for the land and wood.

The number of trees across the world is decreasing sharply. A lot of forests have been destroyed for land and agriculture. As a result, many animals have become endangered species and air pollution has increased.

We must understand the fact that trees are an important part of our ecosystem. They help us in many ways and make our Earth a place to live. We should treat the trees with proper care. If you can, try to plant as many trees as possible around your home. Also, explain to others about the importance of trees.

Fun Facts

Trees use carbon dioxide to produce food. A single tree can consume about 21 kg (48 pounds) of carbon dioxide each year.
Trees excrete water from their leaves which evaporates. As a result, the temperature of its surroundings is reduced.
Trees work as filters for the rainwater.

Nature has a wide range of plant species and they are classified into flowering plants and non-flowering plants. Flowering plants are famous for their beautiful flowers, but non-flowering plants are different in many aspects. Some examples of non-flowering plants are mosses, junipers, cedars, and redwood.

What Are Non-Flowering Plants?

Plants that don’t produce flowers are simply called non-flowering plants. These plants are different in many aspects from flowering plants, but the main difference is in their reproduction. Flowering plants produce flowers for their reproduction. But, non-flowering plants can produce from seeds as well as from spores.

Types of Non-Flowering Plants

Non-flowering plants are divided into two main types according to their reproduction process. One type is called gymnosperm which reproduces itself from seeds. Whereas, the second type contains spore-producing plants.

Gymnosperms – Seed-Producing Non-Flowering Plants

Gymnosperms reproduce from seeds similar to flowering plants. However, these seeds are different and are not enclosed in an ovary or fruit. But, their seeds, also known as naked seeds, are open in the air without any covering.

One of the main groups of gymnosperms is called conifers. Conifers produce seeds when the pollen from a male cone reaches the female cones. Conifers stock their seeds in the cones. When the seeds reach the rich soil, they germinate and grow. Examples of conifers are pines, cypresses, and redwoods.

Spore-Producing Plants

spores-of-fern — Spores of fern on its leaves

This group of non-flowering plants doesn’t produce seeds from reproduction. Instead, they use the spores for their reproduction. The spore-producing plants can be divided into ferns and mosses.

What Are Spores?

Spores are very small organisms consisting of single or multiple cells, housed in a hard coating. Spores are very tiny and are produced in large quantities. They are easily dragged by the wind and moved to far distances. When spores reach the moist place, they germinate and start to grow. Examples of plants that produce spores are mosses, horsetails, and ferns.

Examples of Non-Flowering Plants

Ferns

Ferns are non-flowering plants that reproduce from their spores and thrive in diverse ecosystems. They are also categorized as vascular plants because they distribute their nutrients throughout their parts by special tissues called xylem and phloem. Ferns have unique leaves, known as fronds, which are made of divided leaves.

They are found worldwide in tropical rainforests, temperate woodlands, and arid regions. Ferns produce their spores in specialized spore casings. When these casings get dried, the spores are released into the air. Traditionally, ferns are cultivated to improve the soil and air quality. Some of the famous fern plants are maidenhair fern, royal fern, and bracken fern.

Mosses

Mosses are small-sized primitive plants that have been thriving on the Earth since 400 million years ago. These are non-vascular plants because they don’t have sophisticated tissues (xylem and phloem) for transportation of nutrients. Instead, they have very simple tissues that are specialized in the transportation of water. Mosses reproduce from spores that emerge on their tips.

There are around 12,000 known species of mosses that grow in dense clumps. Mosses are soft and tiny plants that can grow up to a few inches tall. Traditionally, people have been using mosses as an insulating material. They are also good absorbents of water and can absorb water more than 20 times their weight.

Horsetail

Horsetail plants are the only surviving genus of the Equisetaceae family – others have become extinct in the past. They got their name inspired by the shape of the horse’s tail. These non-flowering plants reproduce from spores and can grow to a height of 26 feet. These plants are sometimes called puzzlegrass and snake grass.

Interesting Facts

Redwoods are the largest non-flowering plants. Also, the largest among other plants.
Spores of some plants are lightweight. They are dispersed by air easily.
Pines are the non-flowering and evergreen plants. They remain green in all seasons.

In the battle for survival, plants are normally seen as passive and inactive creatures against their predators called herbivores (plants-eating animals). However, that’s not true! Plants have developed basic and sophisticated defenses against herbivores and pathogenic infections. These defenses help plants to deter herbivores and sometimes become lethal for them.

Types of Plant Defenses

Some factors affect the survivability of plants directly. Among them, the main factors are animals that rely on plants for food, pathogens, parasites, and environmental stress. Plants have developed various defense mechanisms to fight for their survival. There are two types of defense mechanisms in plants.

Constitutive Defenses
Induced Defenses

Constitutive Defenses

These defenses are always present in the plant whether they are being attacked or not. These defenses are basic and protect the plant against herbivores, pathogens, and environmental conditions. There are many types of constitutive defenses, some of them are:

Chemical Defenses: Chemical defenses have been developed in many plants that can make herbivores very sick, sometimes killing them. Poison Ivy is a plant that releases an oil-like liquid that can give its attacker an itchy rash.
Physical Barriers: Plants have developed many types of structures that act as physical barriers against herbivores, for example, spines, thorns, and tough leaves.
Mimicry: Plants have learned the behaviors and taste preferences of herbivores. They have evolved to blend with their environment and mimic the features of inedible objects to avoid being eaten.
Digestive Inhibitors: Many species of plants have developed certain compounds in their leaves which disturbs the digestion process of herbivores when eaten. As a result, herbivores avoid eating such plants.

Induced Defenses

These defenses are triggered when plants are attacked, damaged by herbivores, or due to environmental stress.

Chemical Signaling: Some plants have learned about the predators of the herbivores. So, when they are attacked, they release a volatile organic chemical that attracts the predators of the herbivores. Moreover, few species of plants can produce poisonous substances in their leaves when they are over-eaten. The poisonous substance can make the herbivores ill and sometimes kill them.
Systematic Acquired Resistance: When plants get infected with pathogens, they develop a state of resistance. Also, they remember the initial point within their system from which pathogens entered. So, next time plants will be better prepared and develop resistance at that point.
Salicylic Acid (SA) Pathway: Plants produce salicylic acid in response to pathogenic infections. The salicylic acid activates certain genes which in turn produce antimicrobial compounds to kill the pathogens.

Examples of Plants With Defenses

Cactus

Cactuses are one of the plants that survive in extreme environmental conditions. They have developed spines on their surface which act as a physical barrier against herbivores. These spines can damage the mouth and face of herbivores. Other than this, Spines also provide shade to the overall cactus which reduces their water evaporation.

Some species of cactus have developed specialized structures, such as glochids. The Glochids are hair-like tiny spines that are easily detachable and stick to the bodies of herbivores when they touch the cactus. These glochids cause minor to severe skin irritation so herbivores avoid such cactuses.

Oak Tree

Many plants cover themselves with bark and stems to prevent insects from reaching inside. Oak trees are one of the plants which use thick and rugged barks for protection from insects. The barks also protect their internal structures from the dry atmosphere and harsh weather conditions.

Wild Tobacco

Wild Tobacco produces a chemical, famous known as nicotine which makes their leaves bitter. The bad taste distracts herbivores and acts as a deterrent. Nicotine is a potential alkaloid that acts as a neurotoxin and affects the nervous system. Moreover, nicotine is very toxic to some insects so these insects stay away from wild tobacco.

Fun Facts

Many drugs that are in use today are made from chemicals, which are used by plants for their protection.
Cotton plants produce a chemical that is used to kill bacteria and fungi.
Plants also use chemical defenses against other plants to prevent them from taking the space around them.
Many plants make predators their friends by sheltering them. These predators hunt the herbivores for their food, saving the plant from being eaten.

Plants have evolved to protect themselves against potential threats of herbivores. They have developed many adaptations including the production of poisonous substances. These poisonous substances can cause itching, vomiting, diarrhea, and even death. The poisonous plants play an important role in nature. Let’s dig in deep!

Why Plants Carry Poison?

The first question that everyone will probably ask about poisonous plants is, why do plants produce poison? Because we think of plants as good creatures that are a primary food source for animals. So why do they want to harm the animals? There are some reasons behind it, let’s discuss them.

The main reason for the plants to produce poisonous substances is to get protection from herbivores. Herbivores (plant eaters) consume the plants to survive. Suppose some herbivores start to eat one plant together, they may consume the whole plant. As a result, the plant will die completely. So, some plants have evolved to produce poisonous substances in them. They produce varying amounts of poison to protect them against herbivory when they are consumed more than an average.

sloth — Sloth is hanging on a mangrove tree

Some plants carry permanent poison to protect themselves from herbivores. For example, the leaves of mangrove trees are poisonous to many herbivores. However, a few herbivores can digest these poisonous leaves, e.g. sloths. Being poisonous means only a few species of animals can eat these leaves which helps mangroves to survive while providing food to limited herbivores.

Uses of Poisonous Plants

Poisons of the plants are of course harmful to animals and humans. But, they are also used by scientists in the preparation of medicines and other applications.

Medical Uses: Traditionally, a plant called Belladonna has been used to relieve muscle spasms due to its analgesic properties. Another plant, Digitalis, has provided the first remedy for cardiac arrest, which helped in strengthening the heartbeat.
Cosmetics: Castor oil is widely used by the cosmetic industry due to its moisturizing properties. The castor oil is extracted from very toxic castor seeds. First, it is filtered from toxic substances and then it is used for cosmetics.
Hunting: People have used the poison of the ‘Buckeye’ plant for hunting fish.

Most Poisonous Plants on Earth

Aconitum Napellus

Aconitum Napellus is one of the most toxic plants that is mostly found in mountainous regions of Asia and Europe. It is a beautiful plant with blue and purple color lobed leaves. It contains many alkaloid substances and one of them is aconitine. This substance can cause death when ingested. In general, a small amount of this plant can cause numbness, vomiting, and death in rare cases.

Castor Bean

Castor bean plants are the fastest-growing shrubs that are mostly found in tropical and subtropical regions of the Earth. These plants are economically important due to the oil which is extracted from their seeds. The castor bean plant itself is not toxic and is safe for herbivores. However, the toxic substances are found in their seeds. They contain ricin, which is a poisonous substance. If the seeds of castor beans are eaten, they may cause vomiting, bloody diarrhea, increased heart rate, low blood pressure, and death in some cases. The toxic substance, ricin, is removed during the oil extraction process to make the oil safer.

Water Hemlock

Water hemlock plants belong to the Apiaceae family and are mostly found in North America. They have a beautiful appearance with small white-colored flowers. They also carry highly toxic substances, including cicutoxin. Most of the Cicutoxin is found in its roots which can cause seizures, respiratory system failure, and even death. Water hemlocks are very similar in appearance to edible plants, so control actions are taken in the US to contain them in certain areas.

Fun Facts

Leaves of the apple tree and its seeds contain ‘cyanide’; a very poisonous chemical.
Unripen potatoes are also poisonous; they may cause vomiting.
Some poisonous plants can cause very intense itching when touched, e.g. Poison Ivy.