A few weeks ago, I was driving home through my neighborhood when I got startled by a deer on a neighbor’s front porch. I only saw it from the corner of my eye, but my heart immediately started to race. I could feel the adrenaline coursing through my veins. Reflexively, I whipped my head around so I could look the dreadful beast full in the face.

As it turns out, I survived. It didn’t pose much of a threat. I was in my car, so I was clearly safe and able to get away if need be. It didn’t appear hostile. It certainly wasn’t charging me or showing any overt aggression.

Also, it was a Christmas decoration.

It all felt rather foolish and I laughed for the last few minutes of the drive to my house. I had just been scared by a plastic, decorative, inanimate reindeer. A symbol of the love and peace of the holiday season made me gasp for air. I’m generally not afraid of deer, especially from inside my car. Still, my run in with Blitzen reminded me that, as sophisticated as we think we are, things like this can scare us and we are all built on the chassis of a lizard.

To make my point, I need you to think about car manufacturing for a minute. Really, any sort of mass production will probably do, but the process of designing and making cars is really helpful for this point. Cars are built from the ground up – wheels, frame, body, and the bits that make it work – and in order to maximize the efficiency of rolling out new models, car companies often use the same basic foundation for bunch of their cars. So from a single frame, VW might build a Golf or a Jetta. You might have a Ford Taurus built on the same basic platform as a Lincoln MKZ. Strip down a basic Toyota and a top-of-the-line Lexus and you will find that they share a lot of their structure with one another.

The same thing is basically true of life on earth, at least in our brains which is what I’m really interested in. As we were evolving, there were some structures that turned out to be super efficient at doing some very basic things. It would be a pain to be constantly thinking about having to breath so our brainstem – what we will call our lizard brain – takes care of that for us. All the basic stuff that keeps our core bodily functions in check and humming along are here in the brainstem. Most of the creatures that you think about as animals have a brainstem.

But, you and I know that not all animals are created equal. Some animals have some added features. Like emotion. It’s known now that the furry cats and dogs that we love so much are capable of showing and experiencing emotion. Fear, joy, connection, isolation, sadness – all have some functional basis in this part of the brain. In fact, all mammals have a limbic system of some sort. The limbic system is like adding features to a base model car. There are structures here that are important for memory and learning. An important part of this area’s function is monitoring the environment. The limbic system is constantly on the lookout. It takes in information from the senses and compares it with past memories to see if there is anything around that might be dangerous or a threat to us.

It’s the limbic system – thank you, amygdala – that was largely responsible for me getting frightened by the reindeer. This part of my brain was checking the stream of information coming from my eyes and found a pattern in my peripheral vision that threw up a red flag and it needed to check into it further. It saw the shadow of a figure with four legs and its head raised and wanted to make sure that it wasn’t some predator looking for a quick meal. My limbic system, as it turns out, didn’t evolve to assess whether I was driving a car or not or whether people would decorate their lawns with pretend animals. Among other things, it evolved to keep me from getting eaten.

Can’t blame the old amygdala for getting freaked out. I don’t understand why people put pretend animals on their lawns either.

And then there are the newest parts of the brain. The neocortex is probably what you think about when you think about the brain. It’s the top part with all of the folds and crevices. To have a neocortex installed is kind of like becoming a self-driving car – fully autonomous. You’re able to take the information in from parts of the brain and make rational – rather than reflexive – decisions. You’re able to pull things out of memory and relive the experience, to reevaluate it in retrospect. You’re able to continue to learn lessons from a single event by replaying it in your mind or by imagining the experience from another person’s perspective. Some parts of the neocortex coordinate what is called executive function. In other words, you can make decisions about what you want to do, what you want to wear or eat, if you’re going to ignore that phone call, or buy roses on the way home from work.

The neocortex is the part of the brain that makes us most human. It’s not exclusive to humans – but we’ve got the most developed version with the most capability. It’s the iPhone 6s Plus of neurological structures.

Our brains are incredible. The one stat I’m about to give you should blow your mind. With all of the brain cells that we have connected to one another, there are more possibilities for connection between brain cells than there are atoms in the known universe. Amazing. Obviously not all of these connections are active, but just the notion that there is the potential for this level of connection should probably make you want to wear a helmet the next time you ride a bicycle.

But here’s the thing I want you to take away. Even with this amazing biological achievement all of this potential in our skulls, we are still built on the common lizard base. Even though we think of ourselves as the Lexus concept car of the future, we’re still built on the frame of a 2013 Camry. Why is this important? It can help us understand why we do things the way that we do. It can help us figure out why when someone looks at us with a scowl we assume they’re angry with us, or why we freeze when we’re surprised, or why we get startled by lawn ornaments.

Let’s look at a few interesting examples and then we’ll get practical. We’ll start with reflexes. One of the cutest things that a human can experience is when a young baby grabs your finger. Truth be told, the baby will grab just about anything that happens into their palm, but when that thing happens to be my index finger, I melt. I usually interpret this as being the kiddo showing affection for me even though I rationally know that this a total reflex that evolved to help the baby grab on to their mom in case they ever had to run through the jungle. That reflex is down in the brain stem. The baby doesn’t have to think any more about grabbing my finger than it does breathing or making it’s heart beat. It just happens and then, later, it doesn’t happen any more.

Reflexes like this one don’t so much fade as much as they get overridden. When a baby is born, there’s very little developed in their brains beyond the essential stuff. But, as the baby experiences the world, seeing faces, flailing their arms, having their parents come running after they cry, the higher, fancy pants parts of the brain start to come online. In doing so, they the neocortex starts to take control of these reflexes, suppressing them at first and then growing new circuitry that will be involved in things like fine motor control of those very same fingers. The obvious assumption is that this lizard-brain reflex is lost after it is no longer needed. But it’s not. It sticks around and it’s one of the cooler ways (other than the fact that we continue to breath and regulate our blood pressure and such) that we know the lizard brain is still important. For those folks who begin to experience the effects of dementia or other neurologically degenerative diseases, one of the symptoms a doctor might check will be for the reemergence of this reflexive behavior.  As brain tissue degenerates and some of the circuitry is lost, the neocortex starts to lose control and the reflex, that has been there for our entire lives, comes back.

This example is not practical in any way, I’ll admit. But it’s awfully cool.

As for more practical examples of why it’s important to keep in mind that we are essentially lower animals with features tacked on, let’s go back to the limbic system. At the heart of the limbic system is the amygdala that we mentioned earlier. The amygdala is a multipurpose part of the brain that handles a lot of things, but we most often think of it in terms of flight of fight. Our limbic system circuitry is incredibly fast and it’s primarily focused on keeping us alive. It processes information from the brain about a hundred times faster than the slower, rational parts of the brain. It’s constantly on alert looking for danger. Like the deer on the porch, it’s checking for objects that seem threatening but it’s doing way more than that. It’s checking everything. It’s checking the faces that we see and trying to figure out if there is any stranger danger. Are they pissed? If they are, I should be cautious because they might lash out at me. Do they look healthy or hungry or hurt? I should keep assessing the situation to make sure I’m not in danger. Are they smiling? Perhaps I can approach? Does the smile appear genuine or is there some subtle cue in their face that makes me think they might be coming for me? (Your limbic system is really astounding at reading all of the various faces that people make). It’s quickly accessing memories of past events, even those that you haven’t thought of in years or that you might be completely unaware of. There is definitely a lot going on.

At any time when it feels in danger, it can press the body’s big red button.

If it seems like we need to get out or if we need to fight, the amygdala has the authority to launch a full-scale response and get our bodies ready for the threat. In addition to all of the physical things that happen, the limbic system can also suppress any rational thought that might prevent us from following the amygdala’s advice. For our conversation right now, this is the key part we need to be aware of.

Our amygdala is jumpy. This is good. It’s helped us survive for tens of thousands of years. If you’ll notice though, unless you’re reading this a jungle right now, we’re not in the jungle anymore. We still face threats but not to the same degree that we did back then. Still, our monitoring circuits chug away playing the same role today as they have done for thousands of years. This is how I can rationally say that I’m not afraid of a plastic deer but also jump when I see one in the corner of my eye.

It might not be incredibly important for me to be aware of how my brain is reacting to inanimate objects, but it is important to know how I’m reacting to others. Remember how in addition to looking for patterns, the amygdala is checking through old memories? When those memories involve past relationships, past arguments, or past trauma, it can have a major impact on your current interactions. When your loving partner comes to you with a concern and speaks in a certain tone or in a way that the amygdala recalls from some bad experience in the past, your rational circuitry might not be able to provide a richer context before your amygdala throws you into a defensive mode. Rationally, you trust you partner, but below the level of rationality – below the complex circuitry of the autonomous car – your amygdala is suspicious of everyone.

When we’re aware of this, it’s absolutely possible to decrease the sensitivity of the limbic system to threat, but it would be harmful if we were to ignore it completely. Meditation and mindfulness for example are great ways at integrating the various parts of the brain so that everyone is on the same page. But this jumpy limbic system part of the circuitry that we have been designed with. We’ve got unbelievable computational power bolted on to a platform that is more animal than human.

As a human race, what we have been able to accomplish is mind-boggling. There is no question that humanity sits securely atop the animal kingdom. There is no end to the list of what humans have been able to do over the course of what amounts to a blip in the timeline of creation. The few thousand years that we have been coming together into what we would now call civilization is less than a blink of an eye in the billions of years that have gone into forming the planet and giving rise to life.

A self-driving car is fundamentally still a car. It has any array of advanced capabilities and circuitry. It’s got sensors and computers and is probably safer than most of the people that I’ve ever driven with. It can think and process an enormous amount of data that is streaming in and make decisions about which routes are most efficient. They were the stuff of science fiction only a few short years ago.

In many ways, though, they’re still just a car.

In many ways, we’re still just animals.

And that brings me back to the iPhone.

The iPhone was invented by an animal – to be fair, an entire team of animals. An animal, subject to a host of innate, survival-focused physical responses, that needs to find food and water before it can do anything else, took the knowledge and experiences of thousands of inventors before himself, and created a device that is capable of amazing things including make millions of people take those same capabilities for granted. An animal learned how to read and to write computer code and manufactured microprocessors and LED screens and figured out how they can all work together. An animal managed to overcome their jumpy limbic system and focused their fancy pants brain-computer on solving all of the problems that might come up in created an iPhone. An animal learned how to communicate with a bunch of other animals in order to coordinate a massive amount of testing, research, and production. Then an animal figured out how he could convince even more animals that they needed to go out and buy one of these iPhones.

And now I have an iPhone.

Humans are incredibly capable. There is so much to be in awe of with the human experience before we even start talking about the things that we have accomplished: Emotions, language, the ability to be aware of what we’re thinking and to change our mind, the ability to think about what someone else is thinking. And yet, we are animals. We are subject to the same urges and motivations and processes that all of our animal brothers and sisters contend with. We are aware of the world on a number of different levels, simultaneously monitoring our environment for danger and being able to rationally distance ourselves from it and think about what it all means.

At least for me, it is both humbling and awe inspiring. It helps me feel connected to the world around me. Knowing that I’m a concept car built on old technology – a human built on an animal foundation – helps me make sense of the world I experience. It gives me perspective on things that might otherwise not make sense. It helps me understand the way that I communicate with other people. It helps me understand our need for connection with each other and the pursuit of faith. It gives me perspective on some of life’s great mysteries.

Not the least of which is understand how I got frightened by a plastic deer.