Eudicots

Many plants have two tiny leaves.

These leaves come from a seed. We see them in apples and trees. They help the plant grow big.

These plants are called eudicots. You can find them in your garden. Sunflowers and dandelions are eudicots.

Many leafy trees are in this group too. Cabbage and maple trees are eudicots.

Scientists look at pollen to find them. This pollen has three tiny grooves. These grooves help the pollen grow.

These special plants are everywhere around us.

Eudicots are a large group of flowering plants. The name means "true dicots." This is because they have two seed leaves when they sprout.

You can find eudicots in many places. Many trees and garden plants are eudicots. Sunflowers and dandelions are in this group. Apples and cabbages are eudicots too. Maple trees are also part of this group.

Scientists use pollen to study these plants. Eudicots have a special kind of pollen. This pollen has three grooves. We call these grooves colpi. These grooves help the pollen grain move. They let the pollen inside out. They also help the grain swell or shrink. Other plants have pollen with only one groove.

These plants have been around for a long time. They split from other plants millions of years ago. Some scientists think this happened 134 million years ago. Fossil records show they were already diverse long ago. Today, eudicots make up over 70% of all flowering plants.

Caption: This pollen has three small grooves.

Eudicots are a huge group of flowering plants. They make up over 70% of all flowering plant species. The name means "true dicotyledons." This name tells us they have two seed leaves when they sprout. These seed leaves are called cotyledons. Most of the plants we see every day belong to this group. You might find them in your garden or a local park.

Scientists identify these plants by looking at their pollen. Eudicot pollen has a very special shape. It has three grooves called colpi. These grooves run along the pollen grain. These openings are called apertures. They act like small doors for the pollen. They allow the pollen to swell or shrink with moisture. They also let the pollen contents exit. Other plants have pollen with only one groove called a sulcus.

Researchers have worked hard to name these plants correctly. In 1991, James A. Doyle and Carol L. Hotton introduced the term "eudicots." They wanted to show how these plants are different from older groups. Before this, people often called them tricolpates. This name refers to the three grooves in the pollen. Now, the term eudicots is used in major systems like APG IV. This system helps scientists organize all flowering plants.

These plants have a very long history on Earth. Scientists use a molecular clock to study their past. This tool suggests eudicots split from other plants about 134 million years ago. Some estimates say the split happened between 155 and 160 million years ago. Fossil records show these plants were already very diverse 121 million years ago. They are a major part of the plant world's story.

You probably eat and see eudicots all the time. Many common foods come from this group. This includes cabbage, apples, and even macadamia nuts. You can see them in flowers like sunflowers and dandelions. Many trees are eudicots too, such as maples. Most leafy trees in mid-latitude areas belong here. Only a few trees, like magnolias, are not eudicots.

Eudicots are a massive group of flowering plants. They belong to a large category called angiosperms. This group makes up over 70% of all known angiosperm species. The name "eudicot" comes from the term "true dicotyledon." This refers to the two seed leaves, or cotyledons, that appear during germination. These plants are essential to life on Earth. They include many of the trees, flowers, and foods we use every day.

Scientists identify eudicots by looking at their pollen grains. These grains have a very specific structure. Eudicots possess three grooves called colpi that run along the polar axis. These grooves are a type of pollen aperture. An aperture is a modification in the pollen wall. These openings serve two main purposes. They allow the pollen contents to exit the grain. They also let the grain swell or shrink based on moisture levels. Other plants, like monocots, usually have monosulcate pollen. This type of pollen has only one groove, called a sulcus.

Understanding the history of these plants requires looking at both fossils and genetics. Evolutionary botanist James A. Doyle and paleobotanist Carol L. Hotton introduced the term "eudicots" in 1991. They wanted to highlight how these plants diverged from earlier, less specialized dicots. Before this, scientists often used the name "tricolpates." This name specifically described the three-groove pollen structure. Today, the term eudicot is used in major classification systems. These include the APG systems, such as APG IV from 2016. These systems help organize the vast diversity of flowering plants into a single family tree.

We can trace the ancient lineage of eudicots using a molecular clock. This tool helps scientists estimate when different plant groups split apart. Calculations suggest the eudicot lineage split from other plants about 134 million years ago. Some estimates place this split even earlier, between 155 and 160 million years ago. The fossil record provides even more evidence of their ancient history. Fossil evidence suggests that basal eudicots were already a very diverse group by 121 million years ago. This shows they have been a major part of the Earth's biology for a very long time.

One fascinating way scientists define eudicots is through their DNA. A specific genetic trait defines this group. It involves the duplication of DELLA protein-encoding genes. This duplication occurred in their most recent common ancestor. This genetic marker helps confirm the evolutionary relationships found in morphological studies. Morphological studies look at physical shapes, such as the tricolpate pollen. By combining physical traits with genetic evidence, botanists can be sure of how these plants are related.

Eudicots are divided into several distinct groups. Scientists often separate them into basal eudicots and core eudicots. The core eudicots are a monophyletic group, meaning they include a common ancestor and all its descendants. A 2010 study suggested the core eudicots can be split further. One group is called Gunnerales. The other is a large group called Pentapetalae. The Pentapetalae is then divided into two main branches. These are the superrosids and the superasterids. Each of these branches contains many smaller, specialized groups.

We interact with eudicots constantly in our daily lives. Many common edible plants belong to this group. You might eat cabbage, apples, or macadamia nuts. Many beautiful flowers are also eudicots, such as sunflowers, dandelions, and forget-me-nots. Most leafy trees found in mid-latitude regions are eudicots, including maples and buttercups. There are exceptions to this rule, however. Trees like the magnolia and the American tulip tree belong to the magnoliids instead. This shows how diverse the world of flowering plants truly is.