diff --git a/history/006_snake/src/main/java/com/gitee/drinkjava2/frog/egg/Egg.java b/history/006_snake/src/main/java/com/gitee/drinkjava2/frog/egg/Egg.java
new file mode 100644
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+++ b/history/006_snake/src/main/java/com/gitee/drinkjava2/frog/egg/Egg.java
@@ -0,0 +1,75 @@
+/*
+ * Copyright 2018 the original author or authors. 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by
+ * applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
+ * OF ANY KIND, either express or implied. See the License for the specific
+ * language governing permissions and limitations under the License.
+ */
+package com.gitee.drinkjava2.frog.egg;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import com.gitee.drinkjava2.frog.Animal;
+import com.gitee.drinkjava2.frog.Env;
+import com.gitee.drinkjava2.frog.brain.Organ;
+import com.gitee.drinkjava2.frog.util.RandomUtils;
+
+/**
+ * Egg is the static structure description of frog, can save as file, to build a
+ * frog, first need build a egg.<br/>
+ * 
+ * 蛋存在的目的是为了以最小的字节数串行化存储Frog,它是Frog的生成算法描述，而不是Frog本身，这样一来Frog就不能"永生"了，因为每一个egg都不等同于
+ * 它的母体， 而且每一次测试，大部分条件反射的建立都必须从头开始训练，类似于人类，无论人类社会有多聪明， 婴儿始终是一张白纸，需要花大量的时间从头学习。
+ * 
+ * @author Yong Zhu
+ * @since 1.0
+ */
+public class Egg implements Serializable {
+	private static final long serialVersionUID = 1L;
+	public int x; // 蛋的x位置
+	public int y; // 蛋的y位置
+
+	public List<Organ> organs = new ArrayList<>();// NOSONAR
+
+	public Egg() {// 无中生有，创建一个蛋，先有蛋，后有蛙
+		x = RandomUtils.nextInt(Env.ENV_WIDTH);
+		y = RandomUtils.nextInt(Env.ENV_HEIGHT);
+	}
+
+	/** Create egg from frog */
+	public Egg(Animal a) { // 下蛋，每个器官会创建自已的副本或变异，可以是0或多个
+		for (Organ organ : a.organs)
+			organs.addAll(Arrays.asList(organ.vary()));
+		x = a.x;
+		y = a.y;
+	}
+
+	/**
+	 * Create a egg by join 2 eggs, x+y=zygote 模拟X、Y 染色体合并，两个蛋生成一个新的蛋， X从Y里借一个器官,
+	 * 不用担心器官会越来越多，因为通过用进废退原则来筛选,没用到的器官会在几代之后被自然淘汰掉
+	 * 器官不是越多越好，因为器官需要消耗能量，器官数量多了，在生存竞争中也是劣势
+	 * 
+	 */
+	public Egg(Egg a, Egg b) {
+		x = a.x;
+		y = a.y;
+		// x里原来的organ
+		for (Organ organ : a.organs)
+			organs.add(organ);
+
+		// 从y里借一个organ
+		int yOrganSize = b.organs.size();
+		if (yOrganSize > 0) {
+			Organ o = b.organs.get(RandomUtils.nextInt(yOrganSize));
+			if (o.allowBorrow())
+				organs.add(o);
+		}
+	}
+
+}