Friday 22 May 2015

The Were-plant by the light of the moon!

 A rather unremarkable and scruffy looking plant studied by two scientists has been dubbed the were-plant after it was discovered that it only pollinates during the light of the full moon in June.  A study Moonlight pollination in the gymnosperm Ephedra (Gnetales) undertaken by Catarina Rydin , Kristina Bolinder, Published, 1 April, 2015, looked at how Ephedra (Gnetales) reproduced and in doing so made a remarkable discovery. The study is the result of four seasons of field studies so far which show a surprise relationship between pollination of one of the study species of plants with the lunar cycle in one of the species that they were studying. This work looks at how the discovery was made and what problems the researchers see for the future of the plant.

 
Ephedra foeminea - Author: Gideon Pisanty (Gidip) - 
- CC BY 3.0




Cycles of the moon

The cycles of the moon are are used by a many animals for a number of reasons such as navigation and communication.  Now researchers have discovered the first known case of a plant that times its reproduction to the cycles of the moon. The plant is a rather modest shrub found in areas around the Mediterranean and is known as Ephedra foeminea though since the discovery of its connection to the moon it has been nick-named the were-plant. This is because the plant is a non-flowering relative of conifers and instead of flowers produces masses of red and yellow cones which during the full moon in July secretes sugary fluid to attract the nocturnal insects which pollinate it.  Read more

Friday 1 May 2015

The ecology of sky islands

A sky island is a mountain that is situated in isolation within an area of lowlands where the environment contrasts greatly to the environment of the uplands of the mountain. Instead of being surrounded by water they are surrounded by low lying land. In a location such as this the environment changes dramatically from the lowlands to the mountain summit.  This results in significant differences evolving in the natural habitat of both lowlands and uplands regions of the mountain. 

"Sky islands",  Santa Catalina Mountains,
 Arizona, USA. - Public Domain

In such places it is not unusual to find species of fauna or flora that are limited to a certain altitudes. Such species of animals and birds may practice vertical migration up or down the mountain as the weather and seasons change in order to find food or shelter. Read more

How the Cascade Mountains were formed

The Cascade Mountain range of North America is part of the Pacific Northwest section of what is often called the “Pacific Ring of Fire“ that circles around the Pacific Ocean. The range first began forming millions of years ago through movement of the earth’s plate and volcanic action with erosion also playing a part.

The Cascade Mountains - Attribution: 
The Pacific Ring of Fire

From south to north the Ring runs around the Pacific Rim including the west coast of South and North America, the Aleutian Islands, and then south to north including Japan, Southeast Asia and New Zealand. This circle a volcanically active area that is also prone to earthquakes.  Read more

The Global Climate System

No matter where one lives on Earth, the weather and climate play important parts in daily life.   The weather is the changing conditions in the atmosphere that occur all around, such as rain, snow, wind or sunshine.

U.S. National Oceanic and Atmospheric Administration

What is climate?

Climate is regional or global and is defined by the long-term averages of the extremes and variations in conditions and temperatures over extended periods of time. The climate system is how the atmospheric conditions are influenced by land and ice masses and oceans and how these affect the surface of the Earth. It is comprised of the following five elements that interact with one another and are influenced by other factors such as the Sun, volcanic eruptions and human.  Read more 

The six big mass extinctions

Through out history Earth has suffered a series of mass extinction events that saw the continuation of life on Earth threatened.  There has also been a number of lesser extinctions  but this work concentrates on the main mass extinction events. First, we will briefly define a mass extinction event and then look at the five most devastating mass extinction events in history. Then the discussion will look at the sixth and ongoing mass extinction event and conclude with thoughts for the future.

 
Artistic depiction  Devonian land and flora - Eduard Riou - Public Domain


What is a mass extinction event?

Each extinction varied in intensity and cause but each time life on Earth adapted, evolved and bounced back. A mass extinction event is a time in history where an extraordinary large number of different species die at the same time or within a limited time

The most well known of these events was the Cretaceous-Tertiary extinction which wiped out most of the dinosaurs. Nevertheless, there have been four other mass extinctions, some more devastating than this event, where half or more of all species were estimated to have died.

The most devastating of these events occurred at the end of the Permian period when 96% of species were wiped out.  This event and the Cretaceous-Tertiary extinction event are the two main mass extinctions so far.

There have also been a number of smaller scale mass extinctions.  For example human activity has caused the extinction of many animal and plant species throughout history and in modern times.  In time these will show in the fossil record as a mass extinction. In fact we are going through a sixth mass extinction of plants and animals caused by humans but how devastating that will prove to be only time can tell.  Read more

What makes a spectacular sunset?

One of the most beautiful and spectacular displays in nature comes towards the end of the day as the sun slowly sinks below the western horizon. As it sinks lower its rays have to travel further through the atmosphere to reach the eyes of the observer.

Light

Light travels in waves which are of different lengths. We normally see light as white, but it is actually made up of different colors. The different colors all have their own wavelength.

Magic


The magic begins as sunlight travels through earth's atmosphere Read more

Gemstones: Agate

Agate is a type of quartz from the chalcedony family.  It is created from seams of quartz that commonly consist of many colors.  It most often forms in veins or in rounded shapes.

Fire Agate - Public Domain
 A hard gem

Agate is a hard gem and is measured from 5 – 7 in the Mohs scale though it has a tendency to fracture.  It is not unusual for small crystals of quartz known as drusy to appear inside a stone enhancing its appearance and giving distinction to individual gemstones. These stones are often cut at an angle and used as a main feature for a jewelry design. Read more

Evidence that the global climate has changed

We know that the global climate has changed because of evidence from a number of factors that is taken and collated by scientists all around the world.  Today, with orbiting satellites and other modern technological instruments and techniques it is now possible measure and record with accuracy how and where changes in climate have taken place in many different parts of the world on a daily basis.   By various means this information is then put together to construct a meaningful insight into what is happening with the global climate. 


The Earth taken by the crew 
of  Apollo 17, NASA - Public Domain

NASA point out that while it is known that the global climate has changed a number of times in the past these were caused by natural changes in the way the planet orbits the Sun resulting in changes to the solar energy levels received on Earth.  With temperatures now rising at an exceptionally unparalleled rate over the last 1300 years they believe the present trend is caused by human activities.  Read more


Looking at the polar lights

In the skies over the polar regions of our planet an amazing natural phenomena  occurs that produces the most spectacular and amazing light shows known as the Aurora borealis (Northern lights) and the Aurora australis ( Southern lights).

AuroraAustralis by Mozasaur - Public Domain
Polar lights

The lights appear over the magnetic poles of the northern and southern hemispheres. Those that appear over the magnetic pole of the northern hemisphere are known as the northern lights or Aurora borealis. Those that appear over the magnetic pole of the southern hemisphere are known as the southern lights or Aurora australis.  Read more

The Amazing Fungi Kingdom!

Fungi are a hugely diverse group of organisms that despite their importance to maintaining the environment on Earth are greatly understudied in comparison to plants and animals.  They are neither plants nor animals and belong to their own kingdom yet are of vital importance to the well-being of both groups.  
 
Red cracking bolete (Boletus chrysenteron) - By Przykuta - CC BY-SA 3.0

 It is uncertain how many species of fungi there are globally.  Estimates range from 700,000 to 5 million so clearly no one really knows. The most widely quoted estimate is 1.5 million which still makes it six times as diverse as flowering plants.  Only about 100,000 species of fungi have so far been described.  

Classifying fungi

Fungi are very important organisms that play a crucial part in the cycle of life on the planet.  They are neither plants, or animals and are given their own kingdom in how life on Earth is classified.  Read more

Looking into the blue sky

On a clear day you look up to the sky and high above and all around is a beautiful shade of light blue which ever way you look. The Sun is a pale yellow so bright that you cannot and should not look at it. As you look towards the horizon the blue gently pales to white. You may be over come with a feeling of wonderment and awe as you gaze around the seemingly limitless pale blue skies.
 
Arne in December - blue skies! - By Ian Kirk - CC BY 2.0
 

Why is the sky blue?

Why is it that the sky is blue and not green, or brown or yellow or any other color, or even one big rainbow? To answer that question you need to know a little bit about the atmosphere surrounding the Earth, a little bit about light and a little bit about something called Rayleigh scattering. To be satisfied with the answer you may to think a little about something else.  Read more

The sixth great mass extinction is already underway!

Over the last 450,000, 000 years the Earth has gone through periods when up to 90% of life on the planet has perished in mass extinctions.  Looking back over such great distances in time makes it difficult for humans to comprehend what happens with mass extinctions.  All we really have is the fossil record, geology, and other sciences to help us understand what happened, by looking at what remains today.  Now for the first time humans can experience at first hand what happens as a mass extinction event unfolds.

Does that sound interesting, fascinating and exciting? For the first time we can scientifically observe, record and chart the progress of this event as it happens, because it is happening in the here and now.

But wait a minute! if it is happening now doesn't that mean we are a part of it ?  Yes it does, and if we are lucky humans just might survive as one of the few remaining species, but do not count on it.


Six month old baby giant panda - by Sheila Lau - Public Domain
 Disappearing biodiversity

Humans do not know for sure how many species of fauna and flora we share the planet with but it is known to be millions.  Although there are about 2 million species known to science it is estimated that there could be 5 to 15 million but could be as much as 100 million species altogether. Clearly there is a huge gap in our knowledge.  Nevertheless it does show there is great biodiversity of life on the planet which biologists believe to be essential to maintain a healthy environment for all living organisms.

Some of these like bacteria and spores we can only see with a microscope. Many of the larger ones we see, we interact with them, we can count and study them and of course there are the ones we like, the cuddly, cute funny ones and the one that taste good.  We have learned how to breed and domesticate animals and plants and keep them in such numbers that they seem safe from any threat of extinction.  For example, cattle, sheep and chickens do not appear to be in danger of extinction as we breed them in their millions, but their existence depends on us. Nevertheless, the situation for many wild species of flora and fauna in the wild is becoming increasingly desperate.  Read more

The Wood-Wide Web: The natural living internet system

Next time you go out for a walk in the woods be careful where you tread because underneath your feet connecting tree to tree, plant to plant, lies a remarkable living network that allows the exchange of information between between individual plants.   This network allows the flora of the forest to send and receive information over distances from plant to plant, connecting a large and varied population of individuals together. In fact, this remarkable network is itself alive and is a web of fungi that grows on the roots of trees and plants connecting them together allowing them to communicate and to even send assistance to each other.  More sinisterly, it also gives some of  the plants and trees connected to the network the ability to commit types of "crime" against other members.  It sounds very similar to the modern global communications system of the internet.  In fact it is a living network of fungi and has been called the Earth's natural internet and many scientists refer to it as The Wood-Wide Web.

Porcini or cep (Boletus edulis) - by © Hans Hillewaer - CC BY-SA 4.0

Fungal connections

We usually think of fungi as mushrooms, toadstools and mould, but these are actually the visible parts called fruits that  are above ground that we see.   Below ground lies a web of fine threads called mycelium.   These threads run from root to root, and plant to plant, linking the roots of a multitude of different plants.  Sometimes plants several meters distant are linked creating a living mesh that can conduct information and nutrients to other members of the web.  It gives them the ability to help each other out, but it can also use it for darker purposes, such as sabotage, or "chemical warfare," and other types of "cyber-crime."   Read more

An introduction to forest gardening

A forest garden is a managed, low-maintenance, sustainable way to produce food and useful products and designed to be beneficial to the environment while serving the needs of humans. It can be part of a permaculture design system for producing food and other useful materials, or can be grown as a separate system. Many ideas used in permaculture are used in the design of a forest garden.

Robert Hart in his forest garden, July 1997 - CC BY-SA 3.0
Quercusrobur (Graham Burnett) at en.wikipedia
 Creating a forest garden

To create a sustainable forest garden considerable a vision of the future and a willingness to work for the benefit future generations of humanity is essential. A well designed forest garden created from scratch does takes a lot of work, a large number of plants and a considerable time for those plants to become established.

When they do become established they can provide a durable and sustainable system for producing food and other materials that humans require for many generations to come. Importantly,  being largely self-sustaining with very low maintenance needs and  when viewed in the long-term forest gardens make excellent and productive investments while providing food and products for the benefit of humans in a very eco-friendly way.  Read more

The Nasa Skylab Program

Skylab was America’s first experimental space station. It was launched by NASA who were also responsible for its operation. 
 
Skylab 3 - NASA - Public Domain
According to NASA there were two main objectives that they wanted to achieve with it. Firstly, they wanted to prove that humans could, live, work and operate in space for long periods of time. Secondly they wanted to extend their knowledge of solar astronomy beyond the limited observations that could be obtained from earth. To achieve these objectives it needed to be designed and built to greatly surpass the working duration of previous missions.  Read more

How humans evolved blue eyes

Human eyes range in color from very dark brown to the palest of blue and is affected by the amounts of a pigment called melanin in the iris. The perception of eye color can also be affected by the prevailing light conditions and the local environment. At Copenhagen University researchers have done a lot of thinking and a lot of research on where people got their blue eyes from and come up with an answer and published their findings in Journal of Human Genetics.
 
A blue human eye - by 8thstar - CC BY-SA 3.0

They have discovered that blues eyes are the result of a single mutation that happened to one person who probably lived some where in what is now Romania around the Black Sea region, around 6,000 to 10,000 years ago. This means that all blue-eyed people in the world today are genetically related to that person and each other.

According to their research, a gene in the chromosome known as OCA2 under went a mutation and can be traced back to one of our ancestors who lived in that region at that time. The researchers say that before this event every one in the world had brown eyes.  Read more

Early settlers to Britain

The question of when Britain was first settled by humans has been the subject of ongoing debate and research for many years.   Exciting new discoveries have changed the assumptions of experts leading them to conclude that Britain was possibly settled much earlier than had previously been thought.

Along the coasts of Norfolk and Suffolk ongoing investigations into an extraordinary cluster of Palaeolithic sites has revealed evidence of human activity going back to around 900,000 years.  This is nearly double the earlier estimates and new research is beginning to shed new light on these early settlers.


 
Happisburgh during the Early Pleistocene - by Philg88  - CC BY 4.0

The peninsula of Britain

Although Britain is famous for being an island today it has not always been one.  In fact until about 8,500 years ago it was a part of a wide peninsula jutting out of the north-west of Europe.  During this time migrating animals and humans had easy access to it. Even so, it was not an easy place for humans to settle.  At that time the local climate swung from being warm and Mediterranean-like to cold polar conditions.  Warm periods when humans could gain a foothold on the peninsula were followed by ice ages that forced them off.  There were 8 - 9 periods of warmth where humans settled on the peninsula but each period was followed by an ice age which forced them to abandon it.  About 12,500 years ago the ice finally receded and waves of pioneering settlers moved onto the peninsula establishing permanent.  Read more

Gemstones: Amethysts

Amethysts are a purple type of quartz and regarded as the most valuable member of the quartz family of precious stones.  The color must be purple though it can vary in hue and shade from mauve, lavender, light lilac, to a deep purple.  The finest quality amethysts are a medium deep purple with flashes of rose color.


The color of amethysts

Amethysts can be found in geodes and in areas of alluvial deposits.   Amethysts are formed in clear quartz where manganese is present.  The depth of purple color results from how much iron is present.   The Mohs scale of hardness scales the hardness of precious stone and amethyst is classed as 7 on this scale.  Read more

Designing a forest garden

A well designed forest garden  can be a productive and important part of a Permaculture, or low-impact living system,providing food or other useful products in an environmentally friendly and sustainable way.

Forest garden diagram by Graham Burnett - CC BY-SA 3.0

A young natural forest is a highly productive and self-sustaining eco-system so in forest garden design the essential principle are to reproduce those attributes for human benefit. Although a natural wild forest may look tangled and the trees placed randomly and haphazardly there is an inherent structure that helps to give it such great productivity.  Because different species of trees and plants grow to different heights a natural vertical structure to the forest evolves.

In forest garden design this is known as ‘layering’ and sometimes these layers are referred to as  ‘storeys’ or ‘stacks.’ This layering can often be seen best at the edges of forests where the height of the trees, shrubs, grasses and other plants diminish in size. 
Read more

Ancient high-altitude human settlements

Newly discovered archaeological sites 2.8 miles (4,500 metres) above sea level, high in the Andes mountains of Peru, have shed new light on the altitudes that archaeologists thought was possible for humans to create permanent settlements. These new discoveries have surprised archaeologists who had previously considered it impossible for humans to settle at such high altitudes.  The existence of the sites at such altitudes reveals that humans managed to adapt to such harsh environments much earlier than had previously been thought.
 
Andes Mountains, South America by David Adam Kess - CC BY-SA 3.0

 High-altitude living

A study published in the magazine Science (24 October 2014) reveals that an archaeological team has discovered artefacts and stone buildings decorated with art works which the researchers say are evidence of continued human settlement at high-altitudes. Kurt Rademaker of the University of Maine, the lead author of the report said, "There are many sites of this age at lower elevations in the Andes, and of course there are older sites [at lower elevations] elsewhere in the world, but there is nothing this old at this elevation."    


At such a high altitude the environment would be exceptionally harsh and difficult to live in.  Settlers would have to cope with cold temperatures, high solar radiation and low oxygen and the researchers are not sure how they managed to survive in such inhospitable places.   Some experts think that the settlers may have genetically adapted to the conditions over thousands of years.  Read more

The Amesbury Archer and his Companion

The discovery of an early Bronze Age burial site in Amesbury, near Stonehenge in Wiltshire, caused much excitement with archaeologists. The remains of two males were found and dubbed the Amesbury Archer and his Companion. They were found at a new housing development in 2002 by Wessex Archaeology. These finds have helped archaeologists built a better picture of the society in the Stonehenge area of Britain during the Bronze Age. They have provided evidence of early metal working and intriguing insights into the movement of people during the Bronze Age.


Stonehenge - by Diego Delso - CC BY-SA 4.0
The Beaker Culture

In doing, so archaeologists have discovered new and important evidence of Beaker Culture society in Britain and Europe that is surprising and intriguing. Archaeologists had thought that the Beaker people had been invaders to Britain from continental Europe. They are named after the shape of the pottery drinking cups they made which were found in many burial sites of that time.

Today many experts think that the Beaker culture was a spreading of commerce and culture rather than an invasion. The finding of the Archer provides evidence that people, goods, new ideas and skills did move from Europe to Britain.  Read more

The Boscombe Bowmen: Another Stonehenge Mystery!

In 2003, while digging a trench for a new water pipe a Beaker burial from the Bronze Age was discovered. Most Bronze Age burials found to date have contained only one or two occupants but unusually this was a mass burial containing the remains of seven people.

The full story of this group of people may never be known but their discovery has thrown new light on the transportation of the bluestones from Wales to Stonehenge. It also reveals new knowledge of the movement and migration of people during the Bronze Age and the spread of commerce around Britain and from Europe.


Stonehenge by Joe Dorward - TheCreator - Public Domain
A group burial

Wessex Archaeology examined the burial and reported that the remains of those found belonged to three adult males, one teenage male and three children. The oldest occupant was a man who was buried with his head to the north, on his side, with his legs curled up.

He had suffered a terrible injury to his left thighbone which had been broken and may have healed to be shorter than the right. It is not known how long he had carried the injury but he had survived to walk with a limp and was thought to be 30 to 45 years of age when he died.  Read more

The North American Lynx (Lynx canadensis)

The North American lynx is the largest species of lynx. They are members of the cat family and one of the bigger North American felines though not as large as the cougar.

Canada lynx by kdee64 (Keith Williams) - Flickr - CC BY 2.0
Four species of lynx

There are four recognised species of lynx world wide. The North American lynx, or Canadian lynx, as it is also known, inhabits Canada, and parts of the USA. The bobcat is found in forests across North America. The Eurasian lynx is found in parts of Europe and much of Asia, and the Iberian lynx of southern Spain.  Read more

The American Mountain Lion (Felis concolor)

The American mountain lion is a power and adaptable predator whose range covers much of the Americas.   It is a member of the Felidae family and is native to North and South America. It is also known by the names of cougar, puma, panther, catamount and other names, depending on the country and region it is found
 
Mountain lion - Public  Domain

A large and solitary cat

Indeed, in the Western Hemisphere this big cat has a far greater range than any other wild land animal ranging from the Yukon, in Canada, down to the southern Andes of South America. A large cat and solitary by nature, after the Jaguar, it is the second heaviest cat in the Americas and the joint fourth in the world with the leopard, following the tiger, lion and jaguar, though it is nearer in relationship to the smaller big cats.  Read more

The African Crested Porcupine (Hystrix africaeaustralis)

The African crested porcupine is usually found in rocky, hill country but they are very adaptable animals who make their home in most types of environment, though there are a few exceptions. Although they have been found at altitudes of 11,480 feet on Mount Kilimanjaro, they are not found in dry, empty deserts or damp forests.

African crested Porcupine - Drew Avery - CC BY 2.0
The largest rodent in Africa

This porcupine is the heaviest and largest rodent found in Africa. They have roundish heads, small eyes and ears and a blunt, stubby muzzle. Their legs are short and strong and there are five toes on each foot with powerful claws.  Read more

How birds learned how to fly

The question of how birds evolved the ability to fly has been an ongoing debate for centuries.  To try and answer this question we will first discuss reasons why birds fly. Then we will look at four different theories that have emerged to attempt to explain how birds took to the skies. Finally, we will briefly discuss what, if any, expert consensus there is about how birds evolved the ability to fly.

A roseate tern - US FWS - Public Domain
Powered flight takes up a lot of energy and many large species use air currents and updrafts to glide and soar so they do not have to flap their wings. This is a good way for them to save energy.  But if flying takes up so much energy why use it at all?  Read more

Bighorn Sheep

Bighorn sheep originated in Siberia crossing the Bering land bridge connecting Siberia to North America. They were once numbered in their millions but by 1900 they had diminished to several thousand in population.

Big Horn Sheep, Jack Barrie by Oregon Department of Transportation - CC BY 2.0
 Three distinct species of bighorn sheep

Genetic testing in recent times has identified three distinct species of bighorn sheep in Siberia and North America. They are Ovis Canadensis, Ovis dalli, and Ovis nivicola, or the Siberian Snow sheep. Of these there are several subspecies which include the Rocky Mountains bighorn sheep and the Sierra Nevada bighorn sheep.  Read more

Cool African Elephants!

The world's largest land mammal is the African elephant. Africans are slightly greater in size than Asian elephants and have larger ears that actually look like the shape of the African continent as shown on a map. The ears of Asian elephants are rounder and smaller.

African Forest elephants - Author: Thomas Breuer - CC BY 2.5
How elephants keep cool

In the hot African climate it is often necessary to cool down. Elephants love water and use their trunks to suck up water and spray over their bodies. They then spray a dust over their skin which helps to protect against the sun.

The trunk of an elephant is very versatile with around 100,000 different muscles and has multiple uses. On the end of the trunk can be found to small limbs like fingers that help with grasping and holding. It is also used to smell, drink and breathe.

African elephants; male and female, also have tusks which they use for stripping bark from trees, and digging for food and water. They are also used by males as weapons when fighting.  Read more

The Rough-legged hawk (Buteo lagopus)

The Rough-legged hawk (Buteo lagopus), is also known as the Rough-legged buzzard and is so called because its legs are completely feathered.  This is thought to help protect from rodent bites when it catches prey.  Similar species to the Rough-legged hawk include the Red-tailed hawk, Turkey vulture, Northern harrier, and the Ferruginous hawk.

Rough-legged Hawk - DickDaniels (http://carolinabirds.org/) - CC BY-SA 3.0
Habitat

In the summer the Rough-legged hawk is found in the tundra and and taiga of the northern parts of North America and Eurasia.  In winter it favors marshes, prairies and agricultural regions of Eurasia and North America.  Read more