Cell: a tiny building block that contains all the information necessary for the survival of any plant or animal. It is also the smallest unit of life Cretaceous Period: the geologic time period that lasted from million years ago to 66 million years ago, and that ended with the asteroid strike that is believed to have caused extinction of the dinosaurs DNA deoxyribonucleic acid : molecular instructions that guide how all living things develop and function Evolutionary tree: or phylogenetic tree a branching structure that shows the evolutionary relationships between different groups of organisms Gymnosperm: a seed-producing plant that doesn't package its seeds within fruits or flowers This Antarctic Pearlwort doesn't look so tough here, but this plant can live in a place that gets as cold as degrees Celsius.
That's colder than degrees Fahrenheit. Image by Liam Quinn. Life is competitive. All of the living things you see around you are the result of their ancestors, who successfully competed for food, water and space for millions of years. Compared to gymnosperms needle-covered plants like pine trees , angiosperms just about rule the world. Angiosperms can live in the blistering desert or the frigid Antarctic, and in evolutionary terms, they are still young.
Where did these angiosperms come from and how did they spread from a new group of species to one of the most widespread and diverse groups of living things in the world? Flash forward 40 million years and BAM!
Instead, we have the big, leafy relatives of our flowering plants: trees that look more like Oaks or Maples. This is an example of a simple evolutionary tree. Click for more information. Okay, I know that 40 million years sounds like a very long time, but it often takes s of millions of years for life on earth to change noticeably. For angiosperms, it took less than 50 million years to kick gymnosperms off their prickly throne and become one of the most common forms of life around.
Living things depend on food for just about everything. Plants need food to grow and to make the seeds that will one day become a whole new plant. Unlike animals though, plants can photosynthesize, or make their own food sugar using sunlight and carbon dioxide. Plants have openings called stomata that let in carbon dioxide. A new study in Ecology Letters reveals the evolutionary trigger which led to early flowering plants gaining a major competitive advantage over rival species, leading to their subsequent boom and abundance.
The study, by Dr Tim Brodribb and Dr Taylor Field of the University of Tasmania and University of Tennessee, used plant physiology to reveal how flowering plants, including crops, were able to dominate land by evolving more efficient hydraulics, or 'leaf plumbing', to increase rates of photosynthesis.
Using measurements of leaf vein density and a linked hydraulic-photosynthesis model, Brodribb and Field reconstructed the evolution of leaf hydraulic capacity in seed plants.
Their results revealed that an evolutionary transformation in the plumbing of angiosperm leaves pushed photosynthetic capacity to new heights. The reason for the success of this evolutionary step is that under relatively low atmospheric C0 2 conditions, like those existing at present, water transport efficiency and photosynthetic performance are tightly linked. Therefore adaptations that increase water transport will enhance maximum photosynthesis, exerting substantial evolutionary leverage over competing species.
Angiosperms and the animals they support have given rise to a terrestrial biota far richer than any that came before. Insect pollination, effective dispersal systems, diversity of growth forms, and many other factors have allowed flowering plants to dominate highly dynamic and species-rich vegetation. Because angiosperms photosynthesize so much, they are some of the best oxygen makers around. Angiosperms have been so successful because of their compact DNA and cells. Angiosperms - you are one magnificent bunch of plants.
What is the most successful flowering plant? Flowering plants, like this crocus, are one of the most successful groups of organisms on Earth. How do gymnosperms reproduce? Male gametes microspores are produced in pollen cones and develop into pollen grains. Some gymnosperm species have male and female cones on the same tree, while others have separate male or female cone producing trees.
Fertilization in gymnosperms occurs when pollen grains contact the female ovule and germinate. Do angiosperms have cones? Gymnosperm seeds are often configured as cones. Do angiosperms have seeds? Angiosperms are vascular plants. Angiosperms can pack more veins and pores into their leaves, maximising their productivity. The researchers say genome-downsizing happened only in the angiosperms, and this was ''a necessary prerequisite for rapid growth rates among land plants''.
For instance, why were flowering plants able to shrink their genomes more than others? And why do ferns and conifers still exist, despite their large genomes and cells? Follow Helen on Twitter. Image source, Getty Images.
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